Update pstat property name

Update pstat property name

Update the pstate commit hash property name based on the
security specification.

Change-Id: Id965150e9a1b17920e9c6339a7bc967e63f6f318
Signed-off-by: Sakthivel Samidurai <sakthivel.samidurai@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/1217
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Sachin Agrawal <sachin.agrawal@intel.com>