[clang] [llvm] [PAC][ELF][AArch64] Encode signed GOT flag in PAuth core info (PR #96159)

[Tomas Matheson via cfe-commits]

https://github.com/tmatheson-arm approved this pull request.

LGTM, just based on what I can see from implementation of the existing bits in the version field.

https://github.com/llvm/llvm-project/pull/96159