Handle error callbacks in retrieving default adapter

Signed-off-by: Corentin Lecouvey <corentin.lecouvey@open.eurogiciel.org>
Finalize registerRFCOMMServiceByUUID implementation.

Replace the async implementation by a sync one.


Signed-off-by: Corentin Lecouvey <corentin.lecouvey@open.eurogiciel.org>