In order to forward and create avdtp error properly for setconf command
we need to have the category, to fix this avdtp_error_t now carries the
category as define in avdtp and a new category is used for errno
(AVDTP_ERRNO).
Headsets for proper disconnecting need to disconnect profiles in specified
order(by ex. disconnect a2dp, then sink and hfp at the end). Instead of
adding separate callbacks for disconnecting each profile, now adding only
one callback in audio/device.c for calling audio disconnect functions in
correct order. New disconnect callback works similarly to dev_disconnect
from audio/device.c
