[clang] [CIR] Upstream support for setjmp & longjmp builtins (PR #178989)

[Ayokunle Amodu via cfe-commits]

ayokunle321 wrote:

@andykaylor I plan to address your comments in the next few days. Just to be clear -  the primary fix would be to be leave "_setjmp" out of this PR?

https://github.com/llvm/llvm-project/pull/178989