[clang] [HLSL] Rewrite semantics parsing (PR #152537)

[Nathan Gauër via cfe-commits]

Keenuts wrote:

Thanks! I'll try to repro and figure out the best solution to fix this, but in the meanting, rolling this back (https://github.com/llvm/llvm-project/pull/157718)

https://github.com/llvm/llvm-project/pull/152537