msm: vidc: Timestamp fixes for 4.9

In v4l2 of kernel 4.9 timestamp structures have changed.
Due to this proper timestamps are not passed and received
from firmware. This change fixes it.

CRs-Fixed: 2012385
Change-Id: I33b5bd4a17266234f382bec08bf63014f7f1a362
Signed-off-by: Vaibhav Deshu Venkatesh <vdeshuve@codeaurora.org>