SDL: Ensure polled axes exist
SDL: Ensure polled axes exist

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