[clang] [PAC] Add support for __ptrauth type qualifier (PR #100830)

[Daniil Kovalev via cfe-commits]

kovdan01 wrote:

> Any other feedback on this patch?
> 
> For those who haven't followed the RFC, the RFC received positive reviews, and we have reached a consensus to move forward with the proposal. https://discourse.llvm.org/t/rfc-ptrauth-qualifier/80710/31

@ahatanak I personally have no new feedback compared to what I've already commented on several months ago, so it looks good to me if someone with pauth context in mind approves it.

https://github.com/llvm/llvm-project/pull/100830