[clang] [CIR] Upstream `AddressSpace` support for `PointerType` (PR #161028)

[David Rivera via cfe-commits]

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@@ -35,4 +35,28 @@ class CIR_DefaultValuedEnumParameter<EnumAttrInfo info, string value = "">
   let defaultValue = value;
 }
 
+def CIR_AddressSpace : CIR_I32EnumAttr<
+  "AddressSpace", "address space kind", [
+  I32EnumAttrCase<"Default", 0, "default">,
+  I32EnumAttrCase<"OffloadPrivate", 1, "offload_private">,
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RiverDave wrote:

I do not have enough context regarding the design. @bcardosolopes  your opinion would be helpful here.

https://github.com/llvm/llvm-project/pull/161028