tools/ratbagd: remove KeyMapping methods
tools/ratbagd: remove KeyMapping methods

Cleanup after afaf3fa83ddeeffce6a911225f7170afeba71be5.

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