Sub: Remove baro_alt and baro_climbrate members

We can get this from baro object directly

ArduSub/Log.cpp

@@ -105,7 +105,7 @@ struct PACKED log_Control_Tuning {
     float    throttle_hover;
     float    desired_alt;
     float    inav_alt;
-    int32_t  baro_alt;
+    float    baro_alt;
     int16_t  desired_rangefinder_alt;
     int16_t  rangefinder_alt;
     float    terr_alt;
@@ -131,7 +131,7 @@ void Sub::Log_Write_Control_Tuning()
         throttle_hover      : motors.get_throttle_hover(),
         desired_alt         : pos_control.get_alt_target() / 100.0f,
         inav_alt            : inertial_nav.get_altitude() / 100.0f,
-        baro_alt            : baro_alt,
+        baro_alt            : barometer.get_altitude(),
         desired_rangefinder_alt   : (int16_t)target_rangefinder_alt,
         rangefinder_alt           : rangefinder_state.alt_cm,
         terr_alt            : terr_alt,
@@ -434,7 +434,7 @@ const struct LogStructure Sub::log_structure[] = {
     { LOG_NAV_TUNING_MSG, sizeof(log_Nav_Tuning),       
       "NTUN", "Qffffffffff", "TimeUS,DPosX,DPosY,PosX,PosY,DVelX,DVelY,VelX,VelY,DAccX,DAccY" },
     { LOG_CONTROL_TUNING_MSG, sizeof(log_Control_Tuning),
-      "CTUN", "Qffffffeccfhh", "TimeUS,ThI,ABst,ThO,ThH,DAlt,Alt,BAlt,DSAlt,SAlt,TAlt,DCRt,CRt" },
+      "CTUN", "Qfffffffccfhh", "TimeUS,ThI,ABst,ThO,ThH,DAlt,Alt,BAlt,DSAlt,SAlt,TAlt,DCRt,CRt" },
     { LOG_PERFORMANCE_MSG, sizeof(log_Performance), 
       "PM",  "QHHIhBHII",    "TimeUS,NLon,NLoop,MaxT,PMT,I2CErr,INSErr,LogDrop,Mem" },
     { LOG_MOTBATT_MSG, sizeof(log_MotBatt),

ArduSub/Sub.cpp

@@ -38,8 +38,6 @@ Sub::Sub(void) :
           loiter_time(0),
           climb_rate(0),
           target_rangefinder_alt(0.0f),
-          baro_alt(0),
-          baro_climbrate(0.0f),
           auto_yaw_mode(AUTO_YAW_LOOK_AT_NEXT_WP),
           yaw_look_at_WP_bearing(0.0f),
           yaw_look_at_heading(0),

ArduSub/Sub.h

@@ -327,8 +327,6 @@ private:
     // The cm/s we are moving up or down based on filtered data - Positive = UP
     int16_t climb_rate;
     float target_rangefinder_alt;      // desired altitude in cm above the ground
-    int32_t baro_alt;            // barometer altitude in cm above home
-    float baro_climbrate;        // barometer climbrate in cm/s
 
     // Turn counter
     int32_t quarter_turn_count;

ArduSub/sensors.cpp

@@ -14,8 +14,6 @@ void Sub::read_barometer(void)
     if (should_log(MASK_LOG_IMU)) {
         Log_Write_Baro();
     }
-    baro_alt = barometer.get_altitude() * 100.0f;
-    baro_climbrate = barometer.get_climb_rate() * 100.0f;
 
     sensor_health.depth = barometer.healthy(depth_sensor_idx);
 }