mc pos ctrl: do not publish att sp in offboard && no position/velocity control

src/modules/mc_pos_control/mc_pos_control_main.cpp

@@ -1391,12 +1391,19 @@ MulticopterPositionControl::task_main()
 			reset_yaw_sp = true;
 		}
 
-		// publish attitude setpoint
-		if (_att_sp_pub > 0) {
-			orb_publish(ORB_ID(vehicle_attitude_setpoint), _att_sp_pub, &_att_sp);
+		/* publish attitude setpoint
+		 * Do not publish if offboard is enabled but position/velocity control is disabled,
+		 * in this case the attitude setpoint is published by the mavlink app
+		 */
+		if (!(_control_mode.flag_control_offboard_enabled &&
+					!(_control_mode.flag_control_position_enabled ||
+						_control_mode.flag_control_velocity_enabled))) {
+			if (_att_sp_pub > 0) {
+				orb_publish(ORB_ID(vehicle_attitude_setpoint), _att_sp_pub, &_att_sp);
 
-		} else {
-			_att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &_att_sp);
+			} else {
+				_att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &_att_sp);
+			}
 		}
 
 		/* reset altitude controller integral (hovering throttle) to manual throttle after manual throttle control */