[clang] [clang][AMDGPU] Clean-up handling of named barrier type (PR #207687)

[Pierre van Houtryve via cfe-commits]

Pierre-vh wrote:

> except as noted in a comment for the restriction on inheritance.

It's because with inheritance, you can add class members.
I think I can just rework this to check all the base classes to check for inherited fields, I will look into it


https://github.com/llvm/llvm-project/pull/207687