net: microchip: sparx5: Add port keyset changing functionality

With this its is now possible for clients (like TC) to change the port
keyset configuration in the Sparx5 VCAPs.

This is typically done per traffic class which is guided with the L3
protocol information.
Before the change the current keyset configuration is collected in a list
that is handed back to the client.

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