Remove redundant skb null check

Remove the redundant null check for skb.
Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/act_api.c

@@ -1473,7 +1473,7 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_ROOT_MAX + 1];
-	u32 portid = skb ? NETLINK_CB(skb).portid : 0;
+	u32 portid = NETLINK_CB(skb).portid;
 	int ret = 0, ovr = 0;
 
 	if ((n->nlmsg_type != RTM_GETACTION) &&