[media] cec: update log_addr[] before finishing configuration

The loop that sets the unused logical addresses to INVALID should be
done before 'configured' is set to true. This ensures that cec_log_addrs
is consistent before it will be used.

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