net: hns3: prevent change MTU when resetting

When resetting, the changing of MTU is not allowed, so this patch
adds checking reset status in hns3_nic_change_mtu() to do that.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hns3_enet.c

@@ -1591,6 +1591,9 @@ static int hns3_nic_change_mtu(struct net_device *netdev, int new_mtu)
 	struct hnae3_handle *h = hns3_get_handle(netdev);
 	int ret;
 
+	if (hns3_nic_resetting(netdev))
+		return -EBUSY;
+
 	if (!h->ae_algo->ops->set_mtu)
 		return -EOPNOTSUPP;