mlxsw: spectrum_trap: Make global arrays const as they should be

The global arrays are treated as const, they should be const, so make
them const.

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>