AP_GPS: change empty constructors out for 'use AP_GPS_Backend::AP_GPS_Backend'

libraries/AP_GPS/AP_GPS_ExternalAHRS.cpp

@@ -21,11 +21,6 @@
 
 #if HAL_EXTERNAL_AHRS_ENABLED
 
-AP_GPS_ExternalAHRS::AP_GPS_ExternalAHRS(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port) :
-    AP_GPS_Backend(_gps, _state, _port)
-{
-}
-
 // Reading does nothing in this class; we simply return whether or not
 // the latest reading has been consumed.  By calling this function we assume
 // the caller is consuming the new data;

libraries/AP_GPS/AP_GPS_ExternalAHRS.h

@@ -29,7 +29,8 @@
 class AP_GPS_ExternalAHRS : public AP_GPS_Backend
 {
 public:
-    AP_GPS_ExternalAHRS(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port);
+
+    using AP_GPS_Backend::AP_GPS_Backend;
 
     bool read() override;
     void handle_external(const AP_ExternalAHRS::gps_data_message_t &pkt) override;

libraries/AP_GPS/AP_GPS_MAV.cpp

@@ -19,11 +19,6 @@
 #include "AP_GPS_MAV.h"
 #include <stdint.h>
 
-AP_GPS_MAV::AP_GPS_MAV(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port) :
-    AP_GPS_Backend(_gps, _state, _port)
-{
-}
-
 // Reading does nothing in this class; we simply return whether or not
 // the latest reading has been consumed.  By calling this function we assume
 // the caller is consuming the new data;

libraries/AP_GPS/AP_GPS_MAV.h

@@ -27,7 +27,8 @@
 
 class AP_GPS_MAV : public AP_GPS_Backend {
 public:
-    AP_GPS_MAV(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port);
+
+    using AP_GPS_Backend::AP_GPS_Backend;
 
     bool read() override;
 

libraries/AP_GPS/AP_GPS_MSP.cpp

@@ -21,11 +21,6 @@
 
 #if HAL_MSP_GPS_ENABLED
 
-AP_GPS_MSP::AP_GPS_MSP(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port) :
-    AP_GPS_Backend(_gps, _state, _port)
-{
-}
-
 // Reading does nothing in this class; we simply return whether or not
 // the latest reading has been consumed.  By calling this function we assume
 // the caller is consuming the new data;

libraries/AP_GPS/AP_GPS_MSP.h

@@ -29,7 +29,8 @@
 class AP_GPS_MSP : public AP_GPS_Backend
 {
 public:
-    AP_GPS_MSP(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port);
+
+    using AP_GPS_Backend::AP_GPS_Backend;
 
     bool read() override;
     void handle_msp(const MSP::msp_gps_data_message_t &pkt) override;