USB: serial: cp210x: add Silicon Labs IFS-USB-DATACABLE IDs

The Silicon Labs IFS-USB-DATACABLE is used in conjunction with for example
the Quint UPSes. It is used to enable Modbus communication with the UPS to
query configuration, power and battery status.

Signed-off-by: Kees Jan Koster <kjkoster@kjkoster.org>
Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>