Provide a device_type information for slave network devices created by
DSA, this is useful for user-space application to easily locate/search
for devices of a specific kind.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>