message: core: remove ununsed call
diff: @@ -214,10 +214,7 @@ void MavlinkFtp::process_mavlink_ftp_message(const mavlink_message_t& msg)
  }
  }
  -MavlinkFtp::~MavlinkFtp()
  -{
  - //_mavlink_request_message_handler.unregister_all_handlers(this);
  -}
  +MavlinkFtp::~MavlinkFtp() {}
  void MavlinkFtp::_process_ack(PayloadHeader* payload)
  {
  