ratbagd: if the action special type is invalid, change to unknown
ratbagd: if the action special type is invalid, change to unknown

This prevents us from sending -1 down the wire as unsigned int.

This may be the cause of https://github.com/libratbag/piper/issues/208

Signed-off-by: Peter Hutterer <b9c50af7afa7642f6f854434cda9ffe54ece8b85@who-t.net>

whot/libratbag,whot/libratbag,libratbag/libratbag,libratbag/libratbag,whot/libratbag,libratbag/libratbag