sound_control: add basic sound control.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>

Conflicts:
	drivers/misc/Makefile
sound_control: update how the new values get applied writing and reading them directly from the tabla registries. This will fix the breakage caused by 4.3.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
sound_control: just some cosmetic changes.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
sound_control: add workaround for sound boost resets. Based on https://github.com/faux123/Nexus_5/commit/33407fd2d63290540eb0054bc7c6611f2080ea8b

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
lock only registers that we use