[compiler-rt] [llvm] Recommit "[FunctionAttrs] deduce attr `cold` on functions if all CG paths call a `cold` function" (PR #105559)

[Marco Elver via llvm-commits]

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

LGTM for UAR test.
I leave it to you if you want to use CHECK-DAG or the current version. I'd err on the side of keeping it closer to the original version, as long as there won't be further changes that result in non-deterministic or constantly changing code gen.

https://github.com/llvm/llvm-project/pull/105559