ASoC: msm: Change ACDB driver to use mutex

Remove all atomic variables and provide greater
safety with mutex. Lock mutex for every access
from userspace to ensure that multiple threads
do not concurrently alter data in shared memory
which is used for Audio & Voice calibration. Also
use mutex to protect from concurrent read and write
for calibration that does not used shared memory.

Change-Id: Ib3f2e46805a83ed7e81d0abae1dde32d610b2ba9
CRs-Fixed: 555762
Signed-off-by: Ben Romberger <bromberg@codeaurora.org>
Signed-off-by: flar2 <asegaert@gmail.com>