msm: cpp: Update reserved field to handle cds

The reserved field needs to be properly copied over.
This will ensure the V4L2 buffer will send the information
to the client properly.

Change-Id: I46a8814449f03f2664103ba8d2843f636a4cb42c
Signed-off-by: Krishnankutty Kolathappilly <kkolat@codeaurora.org>
Signed-off-by: Rajakumar Govindaram <rajakuma@codeaurora.org>