audio:should stop btsco when client died

1.app start btsco ,it will use bt-sco preferrer device
2.kill app process,currently only client is removed without closing sco

Signed-off-by: liuxiaoyu7 <liuxiaoyu7@xiaomi.com>
Change-Id: I0738a7f8dee16ea68f7de012c5d7020387f160f9
Merged-In: I381537f61740f9a9fcbf3232ef4336943b0826c5