ekf2: get the rad to deg conversion right

src/modules/ekf2/ekf2_main.cpp

@@ -376,8 +376,8 @@ void Ekf2::task_main()
 		lpos.xy_global =
 			_ekf->position_is_valid();// true if position (x, y) is valid and has valid global reference (ref_lat, ref_lon)
 		lpos.z_global = true;// true if z is valid and has valid global reference (ref_alt)
-		lpos.ref_lat = _ekf->_posRef.lat_rad * (double)180.0 * M_PI; // Reference point latitude in degrees
-		lpos.ref_lon = _ekf->_posRef.lon_rad * (double)180.0 * M_PI; // Reference point longitude in degrees
+		lpos.ref_lat = _ekf->_posRef.lat_rad * 180.0 / M_PI; // Reference point latitude in degrees
+		lpos.ref_lon = _ekf->_posRef.lon_rad * 180.0 / M_PI; // Reference point longitude in degrees
 		lpos.ref_alt =
 			_ekf->_gps_alt_ref; // Reference altitude AMSL in meters, MUST be set to current (not at reference point!) ground level