[clang] [CIR] Model cir.is_fp_class flags as a bit-enum (PR #205941)

[Henrich Lauko via cfe-commits]

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@@ -26,6 +26,12 @@ class CIR_I64EnumAttr<string name, string summary, list<I64EnumAttrCase> cases>
   let cppNamespace = "::cir";
 }
 
+class CIR_I32BitEnumAttr<string name, string summary,
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xlauko wrote:

@andykaylor just namespace 

https://github.com/llvm/llvm-project/pull/205941