[NET_SCHED]: Propagate nla_parse return value

nla_parse() returns more detailed errno codes, propagate them back on
error.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index aaf5049..3228cc4 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -531,8 +531,9 @@
 	if (opt == NULL)
 		return handle ? -EINVAL : 0;
 
-	if (nla_parse_nested(tb, TCA_U32_MAX, opt, NULL) < 0)
-		return -EINVAL;
+	err = nla_parse_nested(tb, TCA_U32_MAX, opt, NULL);
+	if (err < 0)
+		return err;
 
 	if ((n = (struct tc_u_knode*)*arg) != NULL) {
 		if (TC_U32_KEY(n->handle) == 0)