AVRCP: Update a2dp playstate after AVRCP connection.

Fix for play status not updated to playing in video streaming
scenario when a2dp play state is updated before AVRCP is
connected. If the avrcp playstatus is not updated as playing,then
remote device cannot pause the video playback.

Change-Id: Iefc82d10fb914972e301a84162d7434eae9e7e1c