[NS] Notification consumer valgrind invalid read/write fix.

[NS] Notification consumer valgrind invalid read/write fix.

Bug: https://jira.iotivity.org/browse/IOT-2373
Change-Id: Ifd3789538c3d368b7ca3da52d274bb7ed531c126
Signed-off-by: Jay Sharma <jay.sharma@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/20831
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Habib Virji <habib.virji@samsung.com>
(cherry picked from commit bdc2263c344879854b914ec5efd0e232137c49c2)
Reviewed-on: https://gerrit.iotivity.org/gerrit/20663
Reviewed-by: Uze Choi <uzchoi@samsung.com>
Reviewed-by: Phil Coval <philippe.coval@osg.samsung.com>
Reviewed-by: George Nash <george.nash@intel.com>