CMakeList: fix SDL+Wayland+Vulkan

[gucio321]

fix #16163

NOTE Please verify carefully this change since I'm not familiar with CMake at all and I could destroy something 😄

[unknownbrackets]

I think this is better, but there was #11536 for some reason. Maybe a case of https://xkcd.com/1172/.

-[Unknown]

[gucio321]

ok, so how should I handle this?

[gucio321]

well, what is the default state of USE_WAYLAND_WSI? is it OFF or just ""?
if so, I can check if it was OFF and if so, skip Wayland detection

[gucio321]

ok, nevermind, I see that cmake doesn't do this way ;-)

[hrydgard]

Hm. Not sure what to do here :)

I feel that ideally we should always build with both X11 and wayland and chose at runtime...

[hrydgard]

Again I'm really not sure why #11536 was desired, but I also don't really see why this PR could be bad. So I'm inclined to merge it...

[TheComputerGuy96]

Any updates on this? It isn't that great having to rebuild PPSSPP with Wayland WSI support if I want to use the Vulkan renderer with Wayland video driver enabled (right now I'm forced to use the OpenGL one with the Arch Linux package) 🐸

[gucio321]

I'll not do anything more here. Waiting for review
CC @hrydgard

[hrydgard]

Just tested on Mac and it doesn't break this time, nice :) Will actually review the code a bit later, gotta run. Wait I think I confused this with the DPI one.