lib: objagg: Fix an error code in objagg_hints_get()

We need to set the error code on this path otherwise we return
ERR_PTR(0) which would result in a NULL dereference in the caller.

Fixes: 9069a381 ("lib: objagg: implement optimization hints assembly and use hints for object creation")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lib/objagg.c

@@ -968,8 +968,10 @@ struct objagg_hints *objagg_hints_get(struct objagg *objagg,
 	if (err)
 		goto err_fillup_hints;
 
-	if (WARN_ON(objagg_hints->node_count != objagg->obj_count))
+	if (WARN_ON(objagg_hints->node_count != objagg->obj_count)) {
+		err = -EINVAL;
 		goto err_node_count_check;
+	}
 
 	return objagg_hints;