net: sched: cls: Fix offloading when ingress dev is vxlan

When using a vxlan device as the ingress dev, we count it as a
"no offload dev", so when such a rule comes and err stop is true,
we fail early and don't try the egdev route which can offload it
through the egress device.

Fix that by not calling the block offload if one of the devices
attached to it is not offload capable, but make sure egress on such case
is capable instead.

Fixes: caa72601 ("net: sched: keep track of offloaded filters [..]")
Reviewed-by: Roi Dayan <roid@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>