py/objtuple: In tuple_cmp_helper, use mp_check_self instead of raising.

Only tuple, namedtuple and attrtuple use the tuple_cmp_helper function,
and they all have getiter=mp_obj_tuple_getiter, so the check here is only
to ensure that the self object is consistent.  Hence use mp_check_self.

py/objtuple.c

@@ -104,10 +104,8 @@ STATIC mp_obj_t mp_obj_tuple_make_new(const mp_obj_type_t *type_in, size_t n_arg
 
 // Don't pass MP_BINARY_OP_NOT_EQUAL here
 STATIC bool tuple_cmp_helper(mp_uint_t op, mp_obj_t self_in, mp_obj_t another_in) {
-    mp_obj_type_t *self_type = mp_obj_get_type(self_in);
-    if (self_type->getiter != mp_obj_tuple_getiter) {
-        mp_raise_TypeError("");
-    }
+    // type check is done on getiter method to allow tuple, namedtuple, attrtuple
+    mp_check_self(mp_obj_get_type(self_in)->getiter == mp_obj_tuple_getiter);
     mp_obj_type_t *another_type = mp_obj_get_type(another_in);
     mp_obj_tuple_t *self = MP_OBJ_TO_PTR(self_in);
     if (another_type->getiter != mp_obj_tuple_getiter) {