Build SwiftShader native package for `win-arm64`

[alexrp]

This can't be done currently because of errors like this:

D:\a\Silk.NET\Silk.NET\build\submodules\SwiftShader\third_party\llvm-10.0\configs\windows\include\llvm\Config\llvm-config.h(44,1): error C1189: #error:  "unknown architecture" [D:\a\Silk.NET\Silk.NET\build\submodules\SwiftShader\build\third_party\llvm-10.0\llvm.vcxproj]

This is happening because of this code in SwiftShader's llvm-config.h which isn't handling Arm64:

https://github.com/google/swiftshader/blob/62c59c41e194c288c06739788bb0aad3c86b19bf/third_party/llvm-10.0/configs/windows/include/llvm/Config/llvm-config.h#L17-L23

Which then causes this error to happen:

https://github.com/google/swiftshader/blob/62c59c41e194c288c06739788bb0aad3c86b19bf/third_party/llvm-10.0/configs/windows/include/llvm/Config/llvm-config.h#L44

This should be fairly easy to patch on our end.

While doing this, we should also consider building SwiftShader with LLVM 16 instead of 10 (the default).

[Perksey]

In our experience upgrading LLVM versions without dedicated engineering effort to do so always has unforeseen consequences. Recommend waiting for upstream to update here.

[alexrp]

Turns out this requires more build hackery than expected. I'll see how annoying the contribution process is and send some patches upstream if it's not too much.

[alexrp]

https://swiftshader-review.googlesource.com/c/SwiftShader/+/73268

[alexrp]

Landed upstream: https://swiftshader.googlesource.com/SwiftShader/+/1eaac56def92dfadfb2f49695c7d3c5cd1e1274d%5E%21/

Just need to wait for the fix to flow to the GitHub mirror, then we can update our submodule and start building for win-arm64.