[clang] [llvm] Delegate __builtin_setjmp SP and FP save to the backend on all targets (PR #186843)

[Pyry Kovanen via llvm-commits]

pkova wrote:

Deleted the SystemZ and ARM `setjmp.ll` tests for being redundant. I also found some more pre-existing setjmp/longjmp tests that reference `@llvm.stacksave` `@llvm.frameaddress` so I modified them to remove the calls.

https://github.com/llvm/llvm-project/pull/186843