[clang] [llvm] [AMDGPU] Adding the amdgpu-num-work-groups function attribute (PR #79035)

[Erich Keane via cfe-commits]

https://github.com/erichkeane commented:

Clang is mostly good, needs an entry in `ReleaseNotes.rst`.  Also, a Clang 'codegen' test for templates (see the example I gave you!) would be helpful as well.

https://github.com/llvm/llvm-project/pull/79035