openvswitch: Fix ovs_vport_cmd_new return value on success

If the pointer does not represent an error then the PTR_ERR
macro may still return a nonzero value.

Signed-off-by: Rich Lane <rlane@bigswitch.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

net/openvswitch/datapath.c

@@ -1691,6 +1691,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	if (IS_ERR(vport))
 		goto exit_unlock;
 
+	err = 0;
 	reply = ovs_vport_cmd_build_info(vport, info->snd_portid, info->snd_seq,
 					 OVS_VPORT_CMD_NEW);
 	if (IS_ERR(reply)) {