[clang] [HLSL] Make HLSLAttributedResourceType canonical and add code paths to convert HLSL types to DirectX target types (PR #110327)

[Greg Roth via cfe-commits]

https://github.com/pow2clk commented:

I'm a bit out of my depth here, but I've been trying to understand Itanium mangling better and I think my suggestion to coalesce the vendor mangled portions is valid at least.

https://github.com/llvm/llvm-project/pull/110327