[media] em28xx: bind PCTV 460e using I2C client

Load PCTV 460e tda10071 demod and a8293 SEC using I2C client bindings.
Remove old unused tda10071 config struct. We are using I2C platform
data now.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>