[lld] [llvm] [lld][MachO] Add ARM64e pointer authentication linking support (PR #188378)

[Daniel Rodríguez Troitiño via llvm-commits]

https://github.com/drodriguez commented:

Skipped some of the bigger files for the moment. Most of my comments for the moment might be considered minor or nit.

https://github.com/llvm/llvm-project/pull/188378