[clang] [clang-tools-extra] [llvm] [llvm][support] Move `make_absolute` from `sys::fs` to `sys::path` (PR #161459)

[Jan Svoboda via llvm-commits]

jansvoboda11 wrote:

I'm open to figuring out better names for these so that they're not distinguished solely by the namespace, but I think that's fine to leave for a future follow-up.

https://github.com/llvm/llvm-project/pull/161459