msm: camera: isp: add acquire hw handler

This change splits the acquire device function into acquire device and
acquire HW function. Acquire device will only return device handle.
Acquire HW will acquire the HW required for the usecase. There is also
a check to ensure backward compatibility.

Change-Id: I436cd91e099d64abe404661b2bb7dfc09161abb1
Signed-off-by: Junzhe Zou <jnzhezou@codeaurora.org>
Signed-off-by: Harsh Shah <harshs@codeaurora.org>