mlxsw: reg: Align existing registers to use extended local_port field

Add support for 10-bit local ports in device registers by making use of the
MLXSW_ITEM32_LP() macro that was added in the previous patch.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>