radv, aco, nir, ac/llvm: Implement VK_INTEL_shader_integer_functions2 for radv.

Mostly a learning exercise, I don't think anything uses the extension in the wild. I still need to test that it actually works, so it's draft for now. Passes all test from https://gitlab.freedesktop.org/DadSchoorse/crucible/-/tree/rebased-intel_shader_integer_functions2 on Renoir.

This is my first time working on the compiler stack so look out for silly mistakes.