[Feature Request] Swap P1 & P2 feature like in NES Core

[Nam-Ereh-Won]

I liked the feature you added in the latest NES core update and would be cool to have it in the SNES Core as well. Super Mario World, Kirby's Dream Course, and Donkey Kong Country are a handful of titles that could benefit from it. Hope this is something you'd have the time and ability to implement!