cpmac: fix compilation failure introduced with netdev_ops conversion

This patch fixes and obvious typo in the netdev_ops initialization:
ndo_so_ioctl should be ndo_do_ioctl.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/cpmac.c

@@ -1097,7 +1097,7 @@ static const struct net_device_ops cpmac_netdev_ops = {
 	.ndo_start_xmit		= cpmac_start_xmit,
 	.ndo_tx_timeout		= cpmac_tx_timeout,
 	.ndo_set_multicast_list	= cpmac_set_multicast_list,
-	.ndo_so_ioctl		= cpmac_ioctl,
+	.ndo_do_ioctl		= cpmac_ioctl,
 	.ndo_set_config		= cpmac_config,
 	.ndo_change_mtu		= eth_change_mtu,
 	.ndo_validate_addr	= eth_validate_addr,