[media] media: i2c: max2175: Add MAX2175 support

This patch adds driver support for the MAX2175 chip. This is Maxim
Integrated's RF to Bits tuner front end chip designed for software-defined
radio solutions. This driver exposes the tuner as a sub-device instance
with standard and custom controls to configure the device.

Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>