6-button gamepad + multitap issue

[negativeExponent]

          > what is exactly the issue on "supergrafx/pce_fast" that we had to do this modifications (if needed?)

Basically in these 2 games I'm testing:

• Street Fighter II': 6-buttons work fine with multitap, if it's OFF however for some reason P2 is still active and P1 controls BOTH P1 and P2, making impossible to play solo pretty much.
• Garou Densetsu Special: 6-buttons is shifted with multitap, making some buttons useless or doing other button action (e.g. VI acts as RUN, III acts as I) and it can cause freezes/crashes/glitches. With multitap OFF P2 is still active and P1 controls P2.

Only PCE and SuperGrafx cores are affected, both games run fine with 6-buttons with PCE Fast core (because that one doesn't have a multitap toggle option I guess).

Originally posted by @bslenul in https://github.com/libretro/RetroArch/issues/15251#issuecomment-1539872081

[anzz1]

Which one of the 5 games released for SuperGrafx uses 6 buttons? Those games mentioned in the comment you quoted are for the PCE, not SGX.

[negativeExponent]

this issue should be fixed... unless its not...