GBA SIO: Update timings based on observation
GBA SIO: Update timings based on observation

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