netdev: restore MTU change operation

alloc_etherdev() used to install a default implementation of this
operation, but it 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/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
index c7d18860..e8d46cc 100644
--- a/drivers/net/ehea/ehea_main.c
+++ b/drivers/net/ehea/ehea_main.c
@@ -3080,6 +3080,7 @@
 	.ndo_poll_controller	= ehea_netpoll,
 #endif
 	.ndo_get_stats		= ehea_get_stats,
+	.ndo_change_mtu		= eth_change_mtu,
 	.ndo_set_mac_address	= ehea_set_mac_addr,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_set_multicast_list	= ehea_set_multicast_list,