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

[Garvit Gupta via cfe-commits]

quic-garvgupt wrote:

@smithp35 , could you pls parallely also review PR - https://github.com/llvm/llvm-project/pull/121831? I added you as reviewer there as well in the beginning and will appreciate your comments/feedback. Thanks!

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