RTL: fill loiter radius in state Climb (#19165)

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

src/modules/navigator/rtl.cpp

@@ -373,6 +373,7 @@ void RTL::set_rtl_item()
 			_mission_item.time_inside = 0.0f;
 			_mission_item.autocontinue = true;
 			_mission_item.origin = ORIGIN_ONBOARD;
+			_mission_item.loiter_radius = _navigator->get_loiter_radius();
 
 			mavlink_log_info(_navigator->get_mavlink_log_pub(), "RTL: climb to %d m (%d m above destination)\t",
 					 (int)ceilf(_rtl_alt), (int)ceilf(_rtl_alt - _destination.alt));