proto: Fix wrong function calls
proto: Fix wrong function calls

The protocol handler used a wrong function name and thus linking
failed. Replace wii__keys with wii__key.

dvdhrm/xwiimote,barracks510/xwiimote,barracks510/xwiimote,AdamLuchjenbroers/xwiimote,dvdhrm/xwiimote,AdamLuchjenbroers/xwiimote,barracks510/xwiimote,barracks510/xwiimote