net: hns: Fix loopback test failed at copper ports

When doing a loopback test at copper ports, the serdes loopback
and the phy loopback will fail, because of the adjust link had
not finished, and phy not ready.

Adds sleep between adjust link and test process to fix it.
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -339,6 +339,7 @@ static int __lb_setup(struct net_device *ndev,
 static int __lb_up(struct net_device *ndev,
 		   enum hnae_loop loop_mode)
 {
+#define NIC_LB_TEST_WAIT_PHY_LINK_TIME 300
 	struct hns_nic_priv *priv = netdev_priv(ndev);
 	struct hnae_handle *h = priv->ae_handle;
 	int speed, duplex;
@@ -365,6 +366,9 @@ static int __lb_up(struct net_device *ndev,
 
 	h->dev->ops->adjust_link(h, speed, duplex);
 
+	/* wait adjust link done and phy ready */
+	msleep(NIC_LB_TEST_WAIT_PHY_LINK_TIME);
+
 	return 0;
 }