packet: remove some pointless conditionals before kfree_skb()

Remove some pointless conditionals before kfree_skb().
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/packet/af_packet.c

@@ -756,8 +756,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
 	spin_unlock(&sk->sk_receive_queue.lock);
 
 	sk->sk_data_ready(sk, 0);
-	if (copy_skb)
-		kfree_skb(copy_skb);
+	kfree_skb(copy_skb);
 	goto drop_n_restore;
 }