AP_AHRS: add set_posvelyaw_source_set

libraries/AP_AHRS/AP_AHRS.h

@@ -186,6 +186,9 @@ public:
     // request EKF yaw reset to try and avoid the need for an EKF lane switch or failsafe
     virtual void request_yaw_reset(void) {}
 
+    // set position, velocity and yaw sources to either 0=primary, 1=secondary, 2=tertiary
+    virtual void set_posvelyaw_source_set(uint8_t source_set_idx) {}
+
     // Euler angles (radians)
     float roll;
     float pitch;

libraries/AP_AHRS/AP_AHRS_NavEKF.cpp

@@ -2339,6 +2339,14 @@ void AP_AHRS_NavEKF::request_yaw_reset(void)
     }
 }
 
+// set position, velocity and yaw sources to either 0=primary, 1=secondary, 2=tertiary
+void AP_AHRS_NavEKF::set_posvelyaw_source_set(uint8_t source_set_idx)
+{
+#if HAL_NAVEKF3_AVAILABLE
+    EKF3.setPosVelYawSourceSet(source_set_idx);
+#endif
+}
+
 void AP_AHRS_NavEKF::Log_Write()
 {
 #if HAL_NAVEKF2_AVAILABLE

libraries/AP_AHRS/AP_AHRS_NavEKF.h

@@ -299,6 +299,9 @@ public:
     // request EKF yaw reset to try and avoid the need for an EKF lane switch or failsafe
     void request_yaw_reset(void) override;
 
+    // set position, velocity and yaw sources to either 0=primary, 1=secondary, 2=tertiary
+    void set_posvelyaw_source_set(uint8_t source_set_idx) override;
+
     void Log_Write();
 
     // check whether external navigation is providing yaw.  Allows compass pre-arm checks to be bypassed