[clang] [clang] Absoultify paths in dependency file output (PR #117458)

[Fangrui Song via cfe-commits]

MaskRay wrote:

There is a typo in the subject. Absoultify => Absolutify. That said, sth like "canonicalize absolute paths " seem more appropriate wrt the changed semantics.

https://github.com/llvm/llvm-project/pull/117458