[clang] [clang] apply clang-tidy's llvm-redundant-casting (NFC) (PR #191322)

[Victor Chernyakin via cfe-commits]

================
@@ -13889,8 +13889,8 @@ class AddressOfFunctionResolver {
       // If we're in C, we need to support types that aren't exactly identical.
       if (!S.getLangOpts().CPlusPlus ||
           candidateHasExactlyCorrectType(FunDecl)) {
-        Matches.push_back(std::make_pair(
-            CurAccessFunPair, cast<FunctionDecl>(FunDecl->getCanonicalDecl())));
+        Matches.push_back(
+            std::make_pair(CurAccessFunPair, FunDecl->getCanonicalDecl()));
----------------
localspook wrote:

```suggestion
        Matches.emplace_back(CurAccessFunPair, FunDecl->getCanonicalDecl());
```

https://github.com/llvm/llvm-project/pull/191322