net: disallow drivers with buggy VLAN accel to register_netdevice()

net: disallow drivers with buggy VLAN accel to register_netdevice()

Instead of jumping aroung bugs that are easily fixed just don't let them in:
affected drivers should be either fixed or have NETIF_F_HW_VLAN_FILTER
removed from advertised features.

Quick grep in drivers/net shows two drivers that have NETIF_F_HW_VLAN_FILTER
but not ndo_vlan_rx_add/kill_vid(), but those are false-positives (features
are commented out).

OTOH two drivers have ndo_vlan_rx_add/kill_vid() implemented but don't
advertise NETIF_F_HW_VLAN_FILTER. Those are:

+ethernet/cisco/enic/enic_main.c
+ethernet/qlogic/qlcnic/qlcnic_main.c

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