[clang] [llvm] [X86] Extend kCFI with a 3-bit arity indicator (PR #121070)

[Sami Tolvanen via cfe-commits]

https://github.com/samitolvanen approved this pull request.

Thank you for adding the command line flag. I agree that this should be sufficient to address compatibility concerns.

https://github.com/llvm/llvm-project/pull/121070