[clang] [CIR] Fix typeinfo linkage and comdat (PR #192721)

[Henrich Lauko via cfe-commits]

================
@@ -1610,6 +1610,8 @@ mlir::Attribute CIRGenItaniumRTTIBuilder::buildTypeInfo(
   cir::GlobalOp gv =
       CIRGenModule::createGlobalOp(cgm, loc, name, init.getType(),
                                    /*isConstant=*/true);
+  gv.setLinkageAttr(
+      cir::GlobalLinkageKindAttr::get(&cgm.getMLIRContext(), linkage));
----------------
xlauko wrote:

isnt this or similar setter enough?

```suggestion
  gv.setLinkage(linkage);
```

https://github.com/llvm/llvm-project/pull/192721