media: cx231xx: Add i2c device analog tuner support

The boards listed below use i2c device drivers and have
tuner_type equal TUNER_ABSENT. This means additional support
is required to enable the analog tuning capability, a case
statement is used to identify these models.

Models with analog tuning enabled:
- CX231XX_BOARD_HAUPPAUGE_930C_HD_1114xx (tested)
- CX231XX_BOARD_HAUPPAUGE_935C (tested)
- CX231XX_BOARD_HAUPPAUGE_955Q (tested)
- CX231XX_BOARD_HAUPPAUGE_975 (tested)
- CX231XX_BOARD_EVROMEDIA_FULL_HYBRID_FULLHD (untested)

The EvroMedia model was added, since it uses the si2157
tuner and the board profile claims it has analog inputs.

Signed-off-by: Brad Love <brad@nextdimension.cc>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>