msm: camera: Fix blank preview issue for 8660.

Decoupling of AXI and VFE is not required for VFE3.1 as multiple
instances are not supported on it.

Change-Id: I58882f949ab7d46f09a4120f0038491a4c9c0b03
Signed-off-by: Azam Sadiq Pasha Kapatrala Syed <akapatra@codeaurora.org>