audio: Support get output device mute in audiohal. [1/2]

PD#SWPL-191790

Problem:
getMute call audiohal api failed.

Solution:
Complete audiohal api called by getMute.

Verify:
yocto.

Change-Id: Idf3f076bbc098ac8761b3cf13e8b034743c065ac
Signed-off-by: yuliang.hu <yuliang.hu@amlogic.com>
2 files changed