[clang] [Clang] Forward `-Xarch_<arch> -Wl,foo` for GPU toolchains (PR #126248)

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dyung wrote:

> > And just now another failure: https://lab.llvm.org/buildbot/#/builders/190/builds/14342
> 
> Honestly, I don't know. I'd say that it's because we don't support offloading on Darwin, but the triple is supposed to be x64. I could probably just set the test to unsupported for darwin since GPU offloading isn't supported there. Hopefully [a32efd8](https://github.com/llvm/llvm-project/commit/a32efd8edc6ec5f80ffa16b3d4e52e6407d5fe99) resolved it.

I'm seeing our internal downstream builder hit the exact same error in this test, but that is building a Windows hosted compiler targeting Windows. Looking at our runs, it seems to have started appearing after your change 479ffe851bda03d7707b5aae633f231980b71344 oddly enough.

https://github.com/llvm/llvm-project/pull/126248