Sub: removed create() method for objects

See discussion here:

  https://github.com/ArduPilot/ardupilot/issues/7331

we were getting some uninitialised variables. While it only showed up in
AP_SbusOut, it means we can't be sure it won't happen on other objects,
so safest to remove the approach

Thanks to assistance from Lucas, Peter and Francisco

ArduSub/AP_Arming_Sub.h

@@ -4,12 +4,12 @@
 
 class AP_Arming_Sub : public AP_Arming {
 public:
-    static AP_Arming_Sub create(const AP_AHRS &ahrs_ref, const AP_Baro &baro, Compass &compass, const AP_BattMonitor &battery) {
-        return AP_Arming_Sub{ahrs_ref, baro, compass, battery};
+    AP_Arming_Sub(const AP_AHRS &ahrs_ref, const AP_Baro &baro, Compass &compass,
+                  const AP_BattMonitor &battery)
+        : AP_Arming(ahrs_ref, baro, compass, battery)
+    {
     }
 
-    constexpr AP_Arming_Sub(AP_Arming_Sub &&other) = default;
-
     /* Do not allow copies */
     AP_Arming_Sub(const AP_Arming_Sub &other) = delete;
     AP_Arming_Sub &operator=(const AP_Baro&) = delete;
@@ -18,12 +18,6 @@ public:
     bool pre_arm_checks(bool report) override;
 
 protected:
-    AP_Arming_Sub(const AP_AHRS &ahrs_ref, const AP_Baro &baro, Compass &compass,
-                  const AP_BattMonitor &battery)
-        : AP_Arming(ahrs_ref, baro, compass, battery)
-    {
-    }
-
     bool ins_checks(bool report) override;
     enum HomeState home_status() const override;
 };

ArduSub/Sub.cpp

@@ -24,7 +24,7 @@ const AP_HAL::HAL& hal = AP_HAL::get_HAL();
   constructor for main Sub class
  */
 Sub::Sub(void)
-    : DataFlash(DataFlash_Class::create(fwver.fw_string, g.log_bitmask)),
+    : DataFlash(fwver.fw_string, g.log_bitmask),
           control_mode(MANUAL),
           motors(MAIN_LOOP_RATE),
           scaleLongDown(1),

ArduSub/Sub.h

@@ -146,10 +146,10 @@ private:
     ParametersG2 g2;
 
     // main loop scheduler
-    AP_Scheduler scheduler = AP_Scheduler::create();
+    AP_Scheduler scheduler;
 
     // AP_Notify instance
-    AP_Notify notify = AP_Notify::create();
+    AP_Notify notify;
 
     // primary input control channels
     RC_Channel *channel_roll;
@@ -162,16 +162,16 @@ private:
     // Dataflash
     DataFlash_Class DataFlash;
 
-    AP_GPS gps = AP_GPS::create();
+    AP_GPS gps;
 
-    AP_LeakDetector leak_detector = AP_LeakDetector::create();
+    AP_LeakDetector leak_detector;
 
     TSYS01 celsius;
-    AP_Baro barometer = AP_Baro::create();
-    Compass compass = Compass::create();
-    AP_InertialSensor ins = AP_InertialSensor::create();
+    AP_Baro barometer;
+    Compass compass;
+    AP_InertialSensor ins;
 
-    RangeFinder rangefinder = RangeFinder::create(serial_manager, ROTATION_PITCH_270);
+    RangeFinder rangefinder{serial_manager, ROTATION_PITCH_270};
     struct {
         bool enabled:1;
         bool alt_healthy:1; // true if we can trust the altitude from the rangefinder
@@ -181,27 +181,27 @@ private:
     } rangefinder_state = { false, false, 0, 0 };
 
 #if RPM_ENABLED == ENABLED
-    AP_RPM rpm_sensor = AP_RPM::create();
+    AP_RPM rpm_sensor;
 #endif
 
     // Inertial Navigation EKF
-    NavEKF2 EKF2 = NavEKF2::create(&ahrs, barometer, rangefinder);
-    NavEKF3 EKF3 = NavEKF3::create(&ahrs, barometer, rangefinder);
-    AP_AHRS_NavEKF ahrs = AP_AHRS_NavEKF::create(ins, barometer, gps, EKF2, EKF3, AP_AHRS_NavEKF::FLAG_ALWAYS_USE_EKF);
+    NavEKF2 EKF2{&ahrs, barometer, rangefinder};
+    NavEKF3 EKF3{&ahrs, barometer, rangefinder};
+    AP_AHRS_NavEKF ahrs{ins, barometer, gps, EKF2, EKF3, AP_AHRS_NavEKF::FLAG_ALWAYS_USE_EKF};
 
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
     SITL::SITL sitl;
 #endif
 
     // Mission library
-    AP_Mission mission = AP_Mission::create(ahrs,
+    AP_Mission mission{ahrs,
             FUNCTOR_BIND_MEMBER(&Sub::start_command, bool, const AP_Mission::Mission_Command &),
             FUNCTOR_BIND_MEMBER(&Sub::verify_command_callback, bool, const AP_Mission::Mission_Command &),
-            FUNCTOR_BIND_MEMBER(&Sub::exit_mission, void));
+            FUNCTOR_BIND_MEMBER(&Sub::exit_mission, void)};
 
     // Optical flow sensor
 #if OPTFLOW == ENABLED
-    OpticalFlow optflow = OpticalFlow::create(ahrs);
+    OpticalFlow optflow{ahrs};
 #endif
 
     // gnd speed limit required to observe optical flow sensor limits
@@ -213,7 +213,7 @@ private:
     // system time in milliseconds of last recorded yaw reset from ekf
     uint32_t ekfYawReset_ms = 0;
 
-    AP_SerialManager serial_manager = AP_SerialManager::create();
+    AP_SerialManager serial_manager;
 
     // GCS selection
     GCS_Sub _gcs; // avoid using this; use gcs()
@@ -252,15 +252,15 @@ private:
     mode_reason_t prev_control_mode_reason = MODE_REASON_UNKNOWN;
 
 #if RCMAP_ENABLED == ENABLED
-    RCMapper rcmap = RCMapper::create();
+    RCMapper rcmap;
 #endif
 
     // board specific config
-    AP_BoardConfig BoardConfig = AP_BoardConfig::create();
+    AP_BoardConfig BoardConfig;
 
 #if HAL_WITH_UAVCAN
     // board specific config for CAN bus
-    AP_BoardConfig_CAN BoardConfig_CAN = AP_BoardConfig_CAN::create();
+    AP_BoardConfig_CAN BoardConfig_CAN;
 #endif
 
     // Failsafe
@@ -327,9 +327,9 @@ private:
     uint32_t nav_delay_time_start;
 
     // Battery Sensors
-    AP_BattMonitor battery = AP_BattMonitor::create();
+    AP_BattMonitor battery;
 
-    AP_Arming_Sub arming = AP_Arming_Sub::create(ahrs, barometer, compass, battery);
+    AP_Arming_Sub arming{ahrs, barometer, compass, battery};
 
     // Altitude
     // The cm/s we are moving up or down based on filtered data - Positive = UP
@@ -347,7 +347,7 @@ private:
     bool input_hold_engaged;
 
     // loop performance monitoring:
-    AP::PerfInfo perf_info = AP::PerfInfo::create();
+    AP::PerfInfo perf_info;
 
     // 3D Location vectors
     // Current location of the Sub (altitude is relative to home)
@@ -408,39 +408,39 @@ private:
     uint16_t mainLoop_count;
 
     // Reference to the relay object
-    AP_Relay relay = AP_Relay::create();
+    AP_Relay relay;
 
     // handle repeated servo and relay events
-    AP_ServoRelayEvents ServoRelayEvents = AP_ServoRelayEvents::create(relay);
+    AP_ServoRelayEvents ServoRelayEvents{relay};
 
     // Camera
 #if CAMERA == ENABLED
-    AP_Camera camera = AP_Camera::create(&relay, MASK_LOG_CAMERA, current_loc, ahrs);
+    AP_Camera camera{&relay, MASK_LOG_CAMERA, current_loc, ahrs};
 #endif
 
     // Camera/Antenna mount tracking and stabilisation stuff
 #if MOUNT == ENABLED
     // current_loc uses the baro/gps soloution for altitude rather than gps only.
-    AP_Mount camera_mount = AP_Mount::create(ahrs, current_loc);
+    AP_Mount camera_mount{ahrs, current_loc};
 #endif
 
     // AC_Fence library to reduce fly-aways
 #if AC_FENCE == ENABLED
-    AC_Fence fence = AC_Fence::create(ahrs);
+    AC_Fence fence{ahrs};
 #endif
 
 #if AVOIDANCE_ENABLED == ENABLED
-    AC_Avoid avoid = AC_Avoid::create(ahrs, inertial_nav, fence, g2.proximity, &g2.beacon);
+    AC_Avoid avoid{ahrs, inertial_nav, fence, g2.proximity, &g2.beacon};
 #endif
 
     // Rally library
 #if AC_RALLY == ENABLED
-    AP_Rally rally = AP_Rally::create(ahrs);
+    AP_Rally rally{ahrs};
 #endif
 
     // terrain handling
 #if AP_TERRAIN_AVAILABLE && AC_TERRAIN
-    AP_Terrain terrain = AP_Terrain::create(ahrs, mission, rally);
+    AP_Terrain terrain{ahrs, mission, rally};
 #endif
 
     // use this to prevent recursion during sensor init