netpoll: fix the skb check in pkt_is_ns

Neighbor Solicitation is ipv6 protocol, so we should check
skb->protocol with ETH_P_IPV6

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Cc: WANG Cong <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index a664f78..df9e6b1 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -742,7 +742,7 @@
 	struct nd_msg *msg;
 	struct ipv6hdr *hdr;
 
-	if (skb->protocol != htons(ETH_P_ARP))
+	if (skb->protocol != htons(ETH_P_IPV6))
 		return false;
 	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + sizeof(struct nd_msg)))
 		return false;