netdev: restore MAC address set and validate operations

alloc_etherdev() used to install default implementations of these
operations, but they must now be explicitly installed in struct
net_device_ops.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/plip.c b/drivers/net/plip.c
index 7a62f78..b79f776 100644
--- a/drivers/net/plip.c
+++ b/drivers/net/plip.c
@@ -270,6 +270,8 @@
 	.ndo_stop		 = plip_close,
 	.ndo_start_xmit		 = plip_tx_packet,
 	.ndo_do_ioctl		 = plip_ioctl,
+	.ndo_set_mac_address	 = eth_mac_addr,
+	.ndo_validate_addr	 = eth_validate_addr,
 };
 
 /* Entry point of PLIP driver.