mlxsw: spectrum: Add support for Policing and Counting action block

Add support for Policing and Counting action block. This action block
will be used to bind counter to TCAM entries.

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