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

[Daniil Kovalev via llvm-commits]

kovdan01 wrote:

> We need MC layer tests to show how `.tlsdescauthcall` directives generate relocations at specific offsets referencing specific symbols. The existing PAUTH tests don't seem to cover offsets or symbols.

@MaskRay Please let me know if a7f087755ba0476da42cc29e7fdf3b36f922d4e1 addresses your concern and if you have any other comments regarding this PR

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