[libclc] [libclc] Update default triple support for AMD and deprecate 32-bit PTX (PR #174415)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

For the libclc developers, what's the expected way to get the spirv / clsprv targets to work? They always result in this failure for me.
```
cd /home/jhuber/Documents/llvm/llvm-project/build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/libclc && /usr/local/bin/llvm-spirv --spirv-max-version=1.1 -o /home/jhuber/Documents/llvm/llvm-project/build/./lib/clang/22/lib/libclc/spirv64-mesa3d-.spv /home/jhuber/Documents/llvm/llvm-project/build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/libclc/obj.libclc.dir/spirv64-mesa3d-/builtins.link.spirv64-mesa3d-.bc
Unknown attribute kind (105) (Producer: 'LLVM22.0.0git' Reader: 'LLVM 22.0.0git')
```

https://github.com/llvm/llvm-project/pull/174415