Fix cppcheck issues in resource-encapsulation dir

Fix cppcheck issues in resource-encapsulation dir

This patch fixes the "(error) Returning reference to auto variable" issue reported
by cppcheck tool in resource-encapsulation/src/resourceContainer/src dir.

Change-Id: Idade3fb288f7571276274cccb30728cf46851ac6
Signed-off-by: Markus Jung <markus.jung@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/3397
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Madan Lanka <lanka.madan@samsung.com>
(cherry picked from commit 3a681a107a78bd3d36201bcd3cbfcb46500cc813)
Reviewed-on: https://gerrit.iotivity.org/gerrit/3473