[llvm] [Transforms][Utils] Add LoopSplitUtils for iteration-space loop splitting (PR #205995)

[Ramkumar Ramachandra via llvm-commits]

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artagnon wrote:

```suggestion
    return Escaping.push_back(Def);
```

Just write a constructor for EscapingValue with just Def? Not sure why we need this trivial function? Is it part of the public API or something? Could inline in header then?

https://github.com/llvm/llvm-project/pull/205995