media: dvb-usb: Add Cinergy S2 PCIe Dual Port support

Terratec Cinergy S2 PCIe Dual is a PCIe device with two tuners that
actually contains two USB devices. The devices are visible in the
lsusb printout.

Bus 004 Device 002: ID 153b:1182 TerraTec Electronic GmbH Cinergy S2 PCIe Dual Port 2
Bus 003 Device 002: ID 153b:1181 TerraTec Electronic GmbH Cinergy S2 PCIe Dual Port 1

The devices use the Montage M88DS3000/M88TS2022 demod/tuner.

Signed-off-by: Dirk Nehring <dnehring@gmx.net>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>