[llvm] [CMake] Enable CMP0179 alongside CMP0156 for deduplication on LLD (PR #116497)

[Aiden Grossman via llvm-commits]

https://github.com/boomanaiden154 approved this pull request.

Seems reasonable enough to me. Someone else should approve this too before landing though.

https://github.com/llvm/llvm-project/pull/116497