Cockpit finds itself when looking for other GCSs controlling the vehicle

This happens when the user refreshes Cockpit. If Cockpit refreshes in less than 2 seconds, the detect-other-gcs-controlling-the-vehicle-through-mavlink-manual-control routine will kick in and find itself from before the refresh, and disable the joystick forwarding.

That behavior was reported already by @Williangalvani and @vshie.