mlxsw: core: Extend MLXSW_RXL_DIS to register disabled trap group

Extend the mlxsw_listener struct to contain trap group for disabled
traps too. Rename the original "trap_group" item to "en_trap_group" as
it represents enabled state. Let both groups be the same for MLXSW_RXL
however extend MLXSW_RXL_DIS to register separate groups for enable and
disable.

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>