Make HQ black boats not eat infantry

[MrDuck557]

Is your feature request related to a problem? Please describe.
I loaded an infantry into a HQ black boat.
When trying to unload it, I wasn't allowed to.
This is not good.

Describe the solution you'd like
Black boats being able to unload, even when the black boat is on illegal terrain. If the black boat managed to get there, it's probably intentional on the map creator's part or some sort of gimmick the player has. My expected behavior is AWBW, where the transport only checks the unit being unloaded.

Describe alternatives you've considered
Black boats not being to load when on illegal terrain, to prevent eating infantry in the first place.