msm: ais: Fix camera start failure

This reverts some part of changes in the file cam_packet_util.c for the
commit 21fbc0b4 ("msm: ais: Validate packet params against cpu buffer
length") to avoid camera start failure.

Change-Id: I6ada2d81ac92c8f936cc080746f968f2f4e43fa8
Signed-off-by: E V Ravi <evenka@codeaurora.org>