Fix vulkan issues on iOS

[Halo-Michael]

Currently, support for vulkan on iOS is very limited. Currently, the method of loading dynamic library is used to enable vulkan support. But in fact, after selecting the vulkan option, PPSSPP cannot call the vulkan module correctly (still using OpenGL), and there is only few records in the log that shows vulkan does work.

#10654 (comment)

And if run directly from xcode to the device, libMoltenVK.dylib may not be signed by the Apple Developer Certificate.
#13766 (comment)
CMakeFile needs to be improved so that Xcode can correctly treat libMoltenVK.dylib as part of the library and sign it correctly, or use libMoltenVK.a to statically compile into PPSSPP.

[hrydgard]

Aren't we still missing code to actually use Vulkan on iOS, in like ViewController.mm? The IOSGraphicsContext only supports OpenGL.

I think statically compiling it in would probably be the best solution, too.

[Halo-Michael]

MoltenVK do have a static framework library file for statically compile. (/Users/(User name)/VulkanSDK/1.2.182.0/MoltenVK/MoltenVK.xcframework/ios-arm64/libMoltenVK.a)
Also, static compilation makes it easier to use non-jailbroken devices for signature installation/testing.

[Halo-Michael]

Also, static compile for macOS is also a good choice.

[unknownbrackets]

I would not be against static compilation for either one, personally. How much bigger would the iOS app get if it were statically compiled?

-[Unknown]

[Halo-Michael]

I would not be against static compilation for either one, personally. How much bigger would the iOS app get if it were statically compiled?

-[Unknown]

I think the total size will not be smaller than using dynamic link library.

[LoveGaming2much]

Does it work now ?

[hrydgard]

While probably not the same cause, making a note here that it was reported by 𝓓𝓞𝓝𝓣𝓑𝓛𝓐𝓜𝓔𝓜𝓔𝓜8 on Discord that Vulkan started crashing a lot on iOS somewhere in this range:

bbb55e9...b96d4aa