wan: dscc4: remove unnecessary pci_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wan/dscc4.c

@@ -699,8 +699,6 @@ static void dscc4_free1(struct pci_dev *pdev)
 	for (i = 0; i < dev_per_card; i++)
 		unregister_hdlc_device(dscc4_to_dev(root + i));
 
-	pci_set_drvdata(pdev, NULL);
-
 	for (i = 0; i < dev_per_card; i++)
 		free_netdev(root[i].dev);
 	kfree(root);