Review feedback

- Fix comment
- Add roundtrip test

Author: mmha

clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp

@@ -755,7 +755,7 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
         cgf.cgm.errorNYI(loc, "fixed point comparisons");
         result = builder.getBool(false, loc);
       } else {
-        // Unsigned integers and pointers.
+        // integers and pointers
         if (cgf.cgm.getCodeGenOpts().StrictVTablePointers &&
             mlir::isa<cir::PointerType>(lhs.getType()) &&
             mlir::isa<cir::PointerType>(rhs.getType())) {