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

[via cfe-commits]

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@@ -8469,7 +8489,7 @@ void Sema::CheckInfNaNFunction(const CallExpr *Call,
     bool IsInfOrIsFinite =
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cor3ntin wrote:

As an aside, this is called on every function call, which seems widely inficient.

can we do something like
```cpp
FPOptions FPO = Call->getFPFeaturesInEffect(getLangOpts());
if(FPO.getNoHonorInfs())
  return;
```

(and remove `FPO.getNoHonorInfs()` in the rest of the function)







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