selftests: mlxsw: resource_scale: Invoke for Spectrum-3

The scale test for Spectrum-2 should be invoked for Spectrum-2 and
Spectrum-3. Add the appropriate device ID.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>