Provided overload to TypeClass::builtinTypeInfo to return true.

Shouldn't almost all types have a builtin typeinfo? Maybe it'd be better to
have the default at true and only overload typedef and friends.

dmd/mtype.h

@@ -640,6 +640,7 @@ struct TypeClass : Type
     int checkBoolean();
     TypeInfoDeclaration *getTypeInfoDeclaration();
     int hasPointers();
+    int builtinTypeInfo();
 
     type *toCtype();
 

gen/typinf.cpp

@@ -224,6 +224,11 @@ int TypeDArray::builtinTypeInfo()
     return next->isTypeBasic() != NULL;
 }
 
+int TypeClass::builtinTypeInfo()
+{
+    return 1;
+}
+
 /* ========================================================================= */
 
 /***************************************