[media] si2168: get rid of own struct i2c_client pointer

We don't need that anymore as same pointer is passed to each
routine via struct dvb_frontend private field.

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

diff --cc drivers/media/dvb-frontends/si2168.c
Simple merge

diff --cc drivers/media/dvb-frontends/si2168_priv.h
Simple merge