mlxsw: spectrum: Replace port_to_module array with array of structs

Store the initial PMLP register configuration into array of structures
instead of just simple array of module numbers.

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