[clang] [amdgpu-arch] Replace use of HSA with reading sysfs directly (PR #116651)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> > @jhuber6 can you comment on "lot of overhead" and if that matters? Also, not sure why the HSA library dependence is a problem. This seems to be exposing amdgpu-arch to more maintenance overhead.
> 

Sometimes the driver will hang and since this is used inside of `clang` to support `--offload-arch=native` I've had cases where the compiler hangs forever, so I added a timeout to keep it from doing that. This removes that possibility. It's faster and since this will be installed on every single LLVM build, not everyone has ROCm so it would be nice for this to work.



https://github.com/llvm/llvm-project/pull/116651