[llvm] [SampleProf][TableGen] Fix -Wrange-loop-construct warnings (NFC) (PR #221472)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> Possibly, but I don't think it's wrong and there are still fixes motivated by it being commited (e.g. [eff7775](https://github.com/llvm/llvm-project/commit/eff777582665d7c076824cec211fe20c6fb154e5), [68f0da5]

Exactly, we're getting fix spam for this spurious warning which probably isn't accurate. Most of these aren't expensive copies 

https://github.com/llvm/llvm-project/pull/221472