[clang] Warning for incorrect useof 'pure' attribute (PR #78200)

[Aaron Ballman via cfe-commits]

================
@@ -11801,6 +11801,26 @@ static bool CheckMultiVersionFunction(Sema &S, FunctionDecl *NewFD,
                                          OldDecl, Previous);
 }
 
+static void CheckFunctionDeclarationAttributesUsage(Sema &S,
----------------
AaronBallman wrote:

```suggestion
static void DiagnoseConstPureAttributeConflicts(Sema &S,
```
The function does something very specific so we might as well give it a more specific name.

https://github.com/llvm/llvm-project/pull/78200