V4L/DVB (6856): zl10353: improve tuning parameters and update register map

Some more I2C traces and a experimentation with register values on
both the ZL10353 and MT352 mean that I can now guess at what more
of the ZL10353 registers do.

Guess at the registers' names (based on the equivalent names in MT352)
and update set_parameters/get_parameters with the new knowledge.

Signed-off-by: Chris Pascoe <c.pascoe@itee.uq.edu.au>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>