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

[Nathan Gauër via cfe-commits]

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@@ -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>];
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Keenuts wrote:

The default value is 1 here no? Doc says default to 0

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