[clang] [Driver] Add support for GCC installation detection in Baremetal toolchain (PR #121829)

[Garvit Gupta via cfe-commits]

quic-garvgupt wrote:

> > Do the fuchsia builders actually produce output on a failure? We seem to just get exit code 1, but no indication of what filecheck had problems with.
> 
> They do; here's a link! Let me know if you have an problems with the Web UI; I can paste things here if so. https://luci-milo.appspot.com/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8711783358287375697/overview

The check lines that are not found in the tests were added as part of different commit ec230aa and not this one. I will be relanding this commit as is here https://github.com/llvm/llvm-project/pull/144640

https://github.com/llvm/llvm-project/pull/121829