message: current_item: check if returned value is ok
diff: @@ -855,7 +855,13 @@ void MAVLinkMissionTransfer::SetCurrentWorkItem::process_mission_current(const m
  _timeout_handler.remove(_cookie);
  _current = mission_current.seq;
  + if (_current >= 0) {
  callback_and_reset(Result::Success);
  + return;
  + }else{
  + callback_and_reset(Result::CurrentInvalid);
  + return;
  + }
  }
  void MAVLinkMissionTransfer::SetCurrentWorkItem::process_timeout()
  