[clang-tools-extra] [clang-tidy][NFC] Apply llvm-redundant-casting check (PR #214024)

[Yanzuo Liu via cfe-commits]

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@@ -91,7 +91,7 @@ static bool isVarPossiblyChanged(const Decl *Func, const Stmt *LoopStmt,
 static bool isVarThatIsPossiblyChanged(const Decl *Func, const Stmt *LoopStmt,
                                        const Stmt *Cond, ASTContext *Context) {
   if (const auto *DRE = dyn_cast<DeclRefExpr>(Cond)) {
-    if (const auto *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
+    if (const auto *VD = DRE->getDecl())
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zwuis wrote:

```suggestion
    if (const ValueDecl *VD = DRE->getDecl())
```


https://github.com/llvm/llvm-project/pull/214024