msm: cam: camera: Add camera core interface

Add camera internal common framework for camera driver. This framework
provides the common internal interface for the camera hardware drivers.

CRs-Fixed: 2018688
Change-Id: I8b6220856b2ff85d687d8085bedb5c8b6544c1a3
Signed-off-by: Rajakumar Govindaram <rajakuma@codeaurora.org>
Signed-off-by: Harsh Shah <harshs@codeaurora.org>
Signed-off-by: Jing Zhou <jzhou70@codeaurora.org>