Added Retroarch and SDL2 patches

[acmeplus]

Several changes:

• RetroArch:
  • Updated to v1.9.6
  • Added S30 patches from @bkacjios repo https://github.com/bkacjios/RetroArch
• SDL2:
  • Added some general rotation patches (works on apps like SDLPoP but still has resolution issues)
  • Added some S30 specific input patches from @bkacjios repo https://github.com/bkacjios/SDL-mirror
  • Added additional cores:
  • mame2000, mame2003, mame2014/2015, mame2016
  • AdvanceMAME