net/sched: Set the net-device for egress device instance

Currently the netdevice field is not set and the egdev instance
is not functional, fix that.

Fixes: 3f55bdda8df ('net: sched: introduce per-egress action device callbacks')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>