GBA SIO: Some lockstep fixes
GBA SIO: Some lockstep fixes

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