selftests: forwarding: tc_actions.sh: add matchall mirror test

Add test for matchall classifier with mirred egress mirror action.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>