net: eliminate meaningless memcpy to data in pskb_carve_inside_nonlinear()

The frags of skb_shared_info of the data is assigned in following loop. It
is meaningless to do a memcpy of frags here.
Signed-off-by: NMiaohe Lin <linmiaohe@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/skbuff.c

@@ -5953,8 +5953,7 @@ static int pskb_carve_inside_nonlinear(struct sk_buff *skb, const u32 off,
 	size = SKB_WITH_OVERHEAD(ksize(data));
 
 	memcpy((struct skb_shared_info *)(data + size),
-	       skb_shinfo(skb), offsetof(struct skb_shared_info,
-					 frags[skb_shinfo(skb)->nr_frags]));
+	       skb_shinfo(skb), offsetof(struct skb_shared_info, frags[0]));
 	if (skb_orphan_frags(skb, gfp_mask)) {
 		kfree(data);
 		return -ENOMEM;