example: update a2dp_source for hxcmod update

a2dp_source_demo: fix warning

example/a2dp_sink/source_demo: add missing cast

example/a2dp_source_demo: use new sbc encoder api

example/a2dp_sink_demo: remove unneeded curly braces

example/a2dp_source_demo: define A2DP_SOURCE_DEMO_PREFERRED_SAMPLING_RATE

example/a2dp_source_demo: show how to set preferred sample rate

example: use sdp_create_service_record_handle() for sdp record and assert sdp record buffer is large enough, fixes #489

avdtp_source: use sample count as timestamp

examples: unify status stdout format

example/a2dp_source_demo: fix build

example/a2dp_source_demo: add command to scan and connect to Bluetooth speaker by class of device

example/a2dp_source_demo: keep selected audio source

example: fix warnings

example: init SM if LE supported to avoid issue with Android Cross-Transport Key-Derivation

license: update text

avrcp_target: set events and companies

avrcp_target: send supported events and companies directly on AVRCP_PDU_ID_GET_CAPABILITIES query, remove callback from the app

avrcp_controller: rename event

avrcp_controller: emit AVRCP_SUBEVENT_ENABLE_NOTIFICATION_COMPLETE

avrcp_controller: automatically query supported events when registering for notifications

Fix warnings

example: remove handling of notification events with INTERIM status

example/a2dp_source_demo: report initial battery and volume status

a2dp demos: remove useless handler for AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED