[llvm] [VPlan] Only use selectVectorizationFactor for cross-check (NFCI). (PR #103033)

[via llvm-commits]

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@@ -9828,21 +9824,19 @@ bool LoopVectorizePass::processLoop(Loop *L) {
   ElementCount UserVF = Hints.getWidth();
   unsigned UserIC = Hints.getInterleave();
 
-  // Plan how to best vectorize, return the best VF and its cost.
-  std::optional<VectorizationFactor> MaybeVF = LVP.plan(UserVF, UserIC);
+  // Plan how to best vectorize,
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ayalz wrote:

```suggestion
  // Plan how to best vectorize.
```

https://github.com/llvm/llvm-project/pull/103033