net: microchip: sparx5: Add KUNIT test of counters and sorted rules

This tests the insert, move and deleting of rules and checks that the
unused VCAP addresses are initialized correctly.

Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>