[llvm] [Dwarf] Support `__ptrauth` qualifier in metadata nodes (PR #82363)

[Jonas Devlieghere via llvm-commits]

https://github.com/JDevlieghere commented:

I'm pretty excited about this patch as this will unblock upstreaming (and testing) some of the `ptrauth` debug info attributes. 

https://github.com/llvm/llvm-project/pull/82363