[clang] [HLSL] Preserve matrix layout as AST storage metadata (PR #225519)

[Deric C. via cfe-commits]

https://github.com/Icohedron commented:

LGTM after addressing @llvm-beanz suggestions for `clang/test/SemaHLSL/matrix_layout_attr.hlsl` 

https://github.com/llvm/llvm-project/pull/225519