[llvm] [mlir] [Dwarf] Support `__ptrauth` qualifier in metadata nodes (PR #83862)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> @dwblaikie Did you want to have a look at this before we merge this? This PR is going to cause quite a bit of conflicts downstream so I would be nice to merge this somewhat early in the week.

*glances* What sort of conflicts/breakages are you expecting? I guess API breaks on DIBuilder for custom frontends? Other things to look out for?

https://github.com/llvm/llvm-project/pull/83862