[clang] [Clang][AArch64] Remove unwarranted 'cannot be used in non-streaming mode' diagnostic. (PR #150592)

[Harald van Dijk via cfe-commits]

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@@ -5988,11 +5988,9 @@ bool clang::IsArmStreamingFunction(const FunctionDecl *FD,
     if (FD->hasAttr<ArmLocallyStreamingAttr>())
       return true;
 
-  if (const Type *Ty = FD->getType().getTypePtrOrNull())
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hvdijk wrote:

This change looks like it should not be necessary for your main bugfix, this change looks like an micro-optimization based on the knowledge that we know `IsArmStreamingFunction` is now never called with a `FunctionDecl` that has a null type, is that right? If so, I do not think that this function should be assuming that. It may be right for all the code that is in Clang, but this function is available in the public headers, we cannot assume that we know all the places where it gets called.

https://github.com/llvm/llvm-project/pull/150592