GBA: Fix GBAInputUnbindKey prototype
GBA: Fix GBAInputUnbindKey prototype

askotx/mgba,sergiobenrocha2/mgba,AdmiralCurtiss/mgba,libretro/mgba,sergiobenrocha2/mgba,Anty-Lemon/mgba,nattthebear/mgba,Iniquitatis/mgba,Anty-Lemon/mgba,mgba-emu/mgba,iracigt/mgba,Anty-Lemon/mgba,zerofalcon/mgba,bentley/mgba,mgba-emu/mgba,AdmiralCurtiss/mgba,askotx/mgba,Touched/mgba,iracigt/mgba,libretro/mgba,Iniquitatis/mgba,sergiobenrocha2/mgba,libretro/mgba,fr500/mgba,askotx/mgba,Iniquitatis/mgba,sergiobenrocha2/mgba,cassos/mgba,mgba-emu/mgba,fr500/mgba,AdmiralCurtiss/mgba,zerofalcon/mgba,cassos/mgba,cassos/mgba,Touched/mgba,iracigt/mgba,MerryMage/mgba,matthewbauer/mgba,MerryMage/mgba,Anty-Lemon/mgba,fr500/mgba,jeremyherbert/mgba,sergiobenrocha2/mgba,libretro/mgba,libretro/mgba,jeremyherbert/mgba,Touched/mgba,jeremyherbert/mgba,MerryMage/mgba,jeremyherbert/mgba,Iniquitatis/mgba,bentley/mgba,matthewbauer/mgba,mgba-emu/mgba,iracigt/mgba,askotx/mgba,zerofalcon/mgba,fr500/mgba,nattthebear/mgba