media: dvbsky: MyGica T230C support

Mygica T230 DVB-T/T2/C USB stick support. It uses the same FX2/Si2168
bridge/demodulator combo as the other devices supported by the driver,
but uses the Si2141 tuner.
Several DVB-T (MPEG2) and DVB-T2 (H.265) channels were tested, as well as
the included remote control.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>