[Bug]: AirspaceControl event handler may get lost when clients disconnect

[jaj22]

The AirspaceControl functionality is triggered by a GetIn EH added in AIVEHInit. This is run locally where the vehicle is created, which for bought or ungaraged rebel vehicles is on a client. If this client then logs off, the GetIn event handler will no longer trigger for any players and AirspaceControl does not run. For example, this allows players to steal ammo crates from airports while in an undercover civilian heli.

This trigger was always in the wrong place. Should be added with GetInMan in initClient instead.