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

[Sander de Smalen 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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sdesmalen-arm wrote:

> given that it was previously valid
It was never previously valid to call it with an object that is still in the process of being defined, we just hid the issue by returning a bogus result.

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