[clang] [clang]Avoid diagnose invalid consteval call for invalid function decl (PR #68646)

[Erich Keane via cfe-commits]

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@@ -18406,9 +18406,10 @@ static void EvaluateAndDiagnoseImmediateInvocation(
       FD = Call->getConstructor();
     else if (auto *Cast = dyn_cast<CastExpr>(InnerExpr))
       FD = dyn_cast_or_null<FunctionDecl>(Cast->getConversionFunction());
-
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erichkeane wrote:

Unrelated change.

https://github.com/llvm/llvm-project/pull/68646