Wrong use of fflush() standard library removed

Wrong use of fflush() standard library removed

Change-Id: Ic78a44f9dec3144de5a043accaa18ca2a0b38b02
Signed-off-by: Manoj Gupta <manoj.g2@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/17033
Reviewed-by: Phil Coval <philippe.coval@osg.samsung.com>
Reviewed-by: Dave Thaler <dthaler@microsoft.com>
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Mats Wichmann <mats@linux.com>
Reviewed-by: Ziran Sun <ziran.sun@samsung.com>
(cherry picked from commit 1e713e21b54b029794a9dd4ac21df5fae8d75177)
Reviewed-on: https://gerrit.iotivity.org/gerrit/21509
Reviewed-by: George Nash <george.nash@intel.com>