Fix unsupported if virtual interface warning (#6558) (#6861)

src/V3Localize.cpp

@@ -192,6 +192,7 @@ class LocalizeVisitor final : public VNVisitor {
             && !nodep->varp()->isStatic()  // Not a static variable
             && !nodep->varp()->isClassMember()  // Statically exists in design hierarchy
             && !nodep->varp()->sensIfacep()  // Not sensitive to an interface
+            && !nodep->varp()->isVirtIface()  // Not interface pointer
             && !nodep->varp()->valuep()  // Does not have an initializer
         ) {
             UINFO(4, "Consider for localization: " << nodep);