[llvm] [SamplePGO] Support -salvage-stale-profile without probes too (PR #86116)

[Krzysztof Pszeniczny via llvm-commits]

amharc wrote:

I don't have commit access, so I can't assign reviewers, but tagging @xur-llvm @wlei-llvm.

https://github.com/llvm/llvm-project/pull/86116