Implement perelman's xinput modification? (perhaps as an optional setting)

[NintendoManiac64]

See:
https://aweirdimagination.net/2019/04/14/emulating-xbox-controllers-using-gamecube-controllers/

And the code itself:
https://git.aweirdimagination.net/perelman/wii-u-gc-adapter/src/branch/feature/mimic-xpad