msm: camera: sensor: Proper handling of race condition in util api

Power count is coming from user space which can be modified due to
access to shared memory. This change scopes the data locally so
as to avoid vulnerability of count being modified by external
means while executing due to being in shared memory.

CRs-Fixed: 3691744.

Change-Id: I57d13435453195f8aab0c9aad4414d290274ff81
Signed-off-by: Shivi Mangal <quic_smangal@quicinc.com>
(cherry picked from commit c9cd5878)