[media] stv0367: Add support for 16Mhz reference clock

The B2100A dvb NIM card from ST has 2x stv0367 demodulators
and 2x TDA18212 silicon tuners, with a 16Mhz crystal. To
get this working properly with the upstream driver we need
to add support for the 16Mhz reference clock.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>