[llvm] [LV][NFC] Improve readability with `bool` instead of `auto` (PR #111532)

[Florian Hahn via llvm-commits]

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@@ -3204,7 +3204,7 @@ void LoopVectorizationCostModel::collectLoopScalars(ElementCount VF) {
 
     // Determine if all users of the induction variable are scalar after
     // vectorization.
-    auto ScalarInd = llvm::all_of(Ind->users(), [&](User *U) -> bool {
+    bool ScalarInd = llvm::all_of(Ind->users(), [&](User *U) -> bool {
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fhahn wrote:

while you are editing the line, might as well drop redundant `llvm::`
```suggestion
    bool ScalarInd = llvm::all_of(Ind->users(), [&](User *U) -> bool {
```

https://github.com/llvm/llvm-project/pull/111532