[clang] [HLSL][SPIRV] Add vk::binding attribute (PR #150957)

[Steven Perron via cfe-commits]

================
@@ -4894,6 +4894,14 @@ def HLSLSV_GroupIndex: HLSLAnnotationAttr {
   let Documentation = [HLSLSV_GroupIndexDocs];
 }
 
+def HLSLVkBinding : InheritableAttr {
+  let Spellings = [CXX11<"vk", "binding">];
+  let Subjects = SubjectList<[HLSLBufferObj, ExternalGlobalVar], ErrorDiag>;
+  let Args = [IntArgument<"Binding">, IntArgument<"Set", 1>];
----------------
s-perron wrote:

I doubled checked. The `1` is not the default value. It is a boolean value that says the argument is optional. The default value is provided when we parse the attribute.

https://github.com/llvm/llvm-project/pull/150957