Add notes regarding linux support

[LeSnake04]

There are 2 extra steps required from my testing:

1. install vcrun2019: protontricks 1007040 vcrun2019 (Not entirely sure if required)
2. add these start options in steam: WINEDLLOVERRIDES="winmm=n,b" %command%

Can you please add these notes to the README, so Linux users know what to do?

[Neyami]

This also applies to the Steam Deck :nodGreen:

[BlueAmulet]

Did you also have to separately install vc2019 runtime?

[Neyami]

Nope! 😄