[clang] [Clang] Refactor uses of `Cand->Function` in SemaOverload.cpp (PR #98965)

[Shafik Yaghmour via cfe-commits]

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@@ -9994,8 +9995,9 @@ Sema::AddArgumentDependentLookupCandidates(DeclarationName Name,
                                    CandEnd = CandidateSet.end();
        Cand != CandEnd; ++Cand)
     if (Cand->Function) {
-      Fns.erase(Cand->Function);
-      if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate())
+      FunctionDecl *CandFunc = Cand->Function;
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shafik wrote:

We use `Fn` elsewhere, we should be consistent with the rest of the file.

https://github.com/llvm/llvm-project/pull/98965