[llvm] Add the 'initialized' attribute langref and support (PR #84803)

[Jan Voung via llvm-commits]

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@@ -94,6 +94,8 @@ class Attribute {
 
   static const unsigned NumIntAttrKinds = LastIntAttr - FirstIntAttr + 1;
   static const unsigned NumTypeAttrKinds = LastTypeAttr - FirstTypeAttr + 1;
+  static const unsigned NumConstRangeListAttrKinds =
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jvoung wrote:

Is this used by anything (if not, can remove)? I don't see the ConstantRangeAttrKind version of it, and hard to see "NumTypeAttrKinds" used

https://github.com/llvm/llvm-project/pull/84803