[media] dib7000p/dib0090: update the driver

This patch intends to update the dib7000p and dib0090 driver in order to
improve the performances.

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