octeon_ep: ensure get mac address successfully before eth_hw_addr_set()

octep_get_mac_addr() can fail because send mbox message failed. If this
happens, octep_dev->mac_addr will be zero. It should not continue to
initialize. Add exception handling for octep_get_mac_addr() to fix it.

Fixes: 862cd65 ("octeon_ep: Add driver framework and device initialization")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/octeon_ep/octep_main.c

@@ -1072,7 +1072,11 @@ static int octep_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	netdev->max_mtu = OCTEP_MAX_MTU;
 	netdev->mtu = OCTEP_DEFAULT_MTU;
 
-	octep_get_mac_addr(octep_dev, octep_dev->mac_addr);
+	err = octep_get_mac_addr(octep_dev, octep_dev->mac_addr);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to get mac address\n");
+		goto register_dev_err;
+	}
 	eth_hw_addr_set(netdev, octep_dev->mac_addr);
 
 	err = register_netdev(netdev);