Sound Control: (Optional) work around for Nexus 4/5 audio issues

(Use this only for devices with audio reset issues)

Also bump version to 3.1

Signed-off-by: Paul Reioux <reioux@gmail.com>

wcd9xxx-core: add register write without mutex protection

This is assuming the calling function will take care of the mutex.

Change-Id: Icabceee0dff9333ec28ec3d37333b8e05af8a0bb
Signed-off-by: Paul Reioux <reioux@gmail.com>
Sound Control: (OPTIONAL) add power amp registers access control as well

Change-Id: Id34dfe845af0d42607453846e062619cf5927445
Signed-off-by: Paul Reioux <reioux@gmail.com>
sound control: add register cache

bump to version 3.2

Change-Id: I4b97a7acb05ac6840c06044b4ccd4b9bc5244c4a
Signed-off-by: Paul Reioux <reioux@gmail.com>