[clang] AMDGPU: Rename and add bf16 support for global_load_tr builtins (PR #86202)

[Stanislav Mekhanoshin via cfe-commits]

rampitec wrote:

> > Do you want to rename intrinsics as well? Because now intrinsic names do not match builtin names.
> 
> Do we have to match builtins with intrinsics? Renaming intrinsics here means we will have to duplicate the intrinsics.

Is that because of the mangling?

https://github.com/llvm/llvm-project/pull/86202