Update mesa

[chyyran]

There's a couple of blockers before we can actually update mesa

• There's a bug in spirv-to-dxil.c right now where SPIR-V capabilities aren't properly set so OpCapability Shader gets rejected. This is bad and should be fixed Fixed upstream
  • https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30731
• Updates to mesa_mako script: https://github.com/SnowflakePowered/spirv-to-dxil-rs/pull/8/commits/7268e7623c3e680d0d694844814ccee3c6353742#diff-afdb8f6229c797f896f21c0b0c7b56ca81cdc78acb736ce9c831253f2ac6c57f
• u_format_gen.h is annoying and needs to be under util/format
• blake3 utilities should be reimplemented in Rust
  • https://github.com/SnowflakePowered/spirv-to-dxil-rs/blob/7268e7623c3e680d0d694844814ccee3c6353742/spirv-to-dxil-sys/src/native.rs
  • We don't want to build a C copy of blake3 in tree, that would be bad.
• investigate https://github.com/RustPython/RustPython/ to pull mesa locally

[chyyran]

I don't mind basing off dxbc-rebase, but that branch needs cleaning up. Will wait until !30731 gets merged and rebase on top of that.