tc: propogate errors from tcf_hash_create

Allow tcf_hash_create to return different errors on estimator failure.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 0453d79..082c520 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -136,8 +136,8 @@
 	if (!pc) {
 		pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
 				     &ipt_idx_gen, &ipt_hash_info);
-		if (unlikely(!pc))
-			return -ENOMEM;
+		if (IS_ERR(pc))
+		    return PTR_ERR(pc);
 		ret = ACT_P_CREATED;
 	} else {
 		if (!ovr) {