net/sched: Fix update of lastuse in act modules implementing stats_update

We need to update lastuse to to the most updated value between what
is already set and the new value.
If HW matching fails, i.e. because of an issue, the stats are not updated
but it could be that software did match and updated lastuse.

Fixes: 5712bf9c ("net/sched: act_mirred: Use passed lastuse argument")
Fixes: 9fea47d9

 ("net/sched: act_gact: Update statistics when offloaded to hardware")
Signed-off-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>