1. Add g_av_with_rc to avrc_tg_init function
2. Remove g_av_open_fail
3. Add comment in API files
4. Add a2dp init & deinit state variable to inidcate a2dp statement
1. Add reaction for a2dp snk & src disconn req when no link up
2. Change state machine set before EVT upto APP layer in some cases
3. Add bool open_fail to choose whether post disconnection evt to app layer