[media] cx23885: Fix TeVii S471 regression since introduction of ts2020

Patch to make TeVii S471 cards use the ts2020 tuner, since ds3000 driver no
longer contains tuning code.

Signed-off-by: Johannes Koch <johannes@ortsraum.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>