[clang] Implement `ByteAddressBuffer` Load/Store methods (PR #176058)

[Helena Kotas via cfe-commits]

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@@ -3330,6 +3348,17 @@ bool SemaHLSL::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
     auto *ResourceTy =
         TheCall->getArg(0)->getType()->castAs<HLSLAttributedResourceType>();
     QualType ReturnType = ResourceTy->getContainedType();
+    // ByteAddressBuffer uses the FunctionDecl return type instead of the
+    // contained type
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hekota wrote:

```suggestion
    // Figure out the return type of the intrinsic. For most resources it
    // is the contained type. For ByteAddressBuffer it is determined by
    // the return value type.
```

https://github.com/llvm/llvm-project/pull/176058