mlxsw: acl: Introduce activity get operation for action block/set

In Spectrum-2, activity cannot be find out by TCAM rule (PTCEv2 register),
but rather by associated action set. For that purpose, extend action ops
to allow query activity from PEFA register. Block activity is decided
according to activity of the first set.

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>