Fix "(unregistered net_device): Features changed" message

Fix netdev_update_features() messages on register time by moving
the call further in register_netdevice(). When
netdev->reg_state != NETREG_REGISTERED, netdev_name() returns
"(unregistered netdevice)" even if the dev's name is already filled.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>