[llvm] [VPlan] Make CanIV part of region. (PR #144803)

[via llvm-commits]

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@@ -4194,8 +4193,9 @@ class VPlan {
   /// Create a new loop VPRegionBlock with \p Name and entry and exiting blocks set
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ayalz wrote:

```suggestion
  /// Create a new loop VPRegionBlock with \p StartV and \p Name, entry and exiting blocks set
```

https://github.com/llvm/llvm-project/pull/144803