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

[Daniel Rodríguez Troitiño via llvm-commits]

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drodriguez wrote:

I did a quick check of the behaviour of `ld` and it seems that it just prints a warning and uses chained fixups instead of failing. Maybe this logic belongs in `shouldEmitChainedFixups` instead?

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