[media] cec: always check all_device_types and features

Even when the adapter is configured for CEC 1.4, we still check and
use the CEC 2.0 parts of struct cec_log_addrs. Although these aren't
used in CEC messages, the information contained in them is still of
use in the CEC framework itself, so keep this information.

Also zero the unused trailing features[] data and unused logical address
data so the contents isn't random data.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>