[llvm] [PAC][ELF] Support R_AARCH64_AUTH_TLSDESC_CALL relocation (PR #198327)

[Daniil Kovalev via llvm-commits]

kovdan01 wrote:

@jrtc27 @MaskRay @smithp35 I would appreciate your feedback on this. Note that the lld PR is stacked on top of the llvm PR and not vice versa because the tests for the lld PR rely on `.tlsauthdesccall` being correctly parsed by assembly. I plan to merge them simultaneously when both are approved.

https://github.com/llvm/llvm-project/pull/198327