net: hns: add skb_reset_mac_header() after skb being alloc

HNS receives a packet without doing anything, but it should call
skb_reset_mac_header() to initialize the header before using
eth_hdr().

Fixes: 0d6b425a3773c3445b0f51b2f333821beaacb619
Signed-off-by: Kejian Yan <yankejian@huawei.com>
Signed-off-by: Yisen Zhuang <Yisen.Zhuang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns/hns_enet.c

@@ -600,6 +600,7 @@ static int hns_nic_poll_rx_skb(struct hns_nic_ring_data *ring_data,
 		ring->stats.sw_err_cnt++;
 		return -ENOMEM;
 	}
+	skb_reset_mac_header(skb);
 
 	prefetchw(skb->data);
 	length = le16_to_cpu(desc->rx.pkt_len);