V4L/DVB (7410): use tuner-simple for Thomson FE6600 digital tuning support

Convert cx88-dvb to use tuner-simple instead of dvb-pll for Thomson FE6600

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>