[media] dib8096: enhancement

The intend of this patch is to improve the support of the dib8096. The PLL
parameters are not automatically computed. The limit to set/unset external
diode for attenuation has been updated. The TFE8096P board is using the
new I2C API.

Signed-off-by: Olivier Grenie <olivier.grenie@parrot.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@parrot.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>