FlexASIO support on windows

[xpufx]

I am not sure if it's already supported or if there's any support to add on the mod-desktop side but it doesn't seem to be picked up as an audio device option in my testing. Asio4all does show up but flexasio does not. I have other software that does pick up both. Information regarding this would be appreciated. This is not strictly a feature request but just a question at this point.