GBA: Fix warning about too old version of a savestate
GBA: Fix warning about too old version of a savestate

Anty-Lemon/mgba,Iniquitatis/mgba,sergiobenrocha2/mgba,libretro/mgba,fr500/mgba,fr500/mgba,Anty-Lemon/mgba,libretro/mgba,jeremyherbert/mgba,Touched/mgba,iracigt/mgba,iracigt/mgba,MerryMage/mgba,Touched/mgba,libretro/mgba,jeremyherbert/mgba,fr500/mgba,mgba-emu/mgba,mgba-emu/mgba,Anty-Lemon/mgba,MerryMage/mgba,Iniquitatis/mgba,fr500/mgba,libretro/mgba,sergiobenrocha2/mgba,iracigt/mgba,mgba-emu/mgba,jeremyherbert/mgba,Anty-Lemon/mgba,iracigt/mgba,Iniquitatis/mgba,sergiobenrocha2/mgba,MerryMage/mgba,sergiobenrocha2/mgba,Touched/mgba,sergiobenrocha2/mgba,jeremyherbert/mgba,mgba-emu/mgba,Iniquitatis/mgba,libretro/mgba