[clang] [Clang] Fix warning for non std functions with name `infinity` (PR #123417)

[Amr Hesham via cfe-commits]

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@@ -8469,7 +8489,7 @@ void Sema::CheckInfNaNFunction(const CallExpr *Call,
     bool IsInfOrIsFinite =
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AmrDeveloper wrote:

Yes, I agree, i am thinking to change the structure of the function `CheckInfNaNFunction ` too, because if `HasIdentifier` is false that's means `IsStdFunction`, `IsInfOrNanFunction` and `IsInfinityFunction` will return false, so maybe we can just eliminate some un needed function calls by early return.

I will try and update you with result :D

https://github.com/llvm/llvm-project/pull/123417