Fix issues reported by SVACE tool in CKM module.

Fix issues reported by SVACE tool in CKM module.

Change-Id: I995b4b6f0f58f9db0be2eb9703a80052b69523b2
Signed-off-by: i.pazderskyy <i.pazderskyy@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/5311
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Dmitriy Zhuravlev <d.zhuravlev@samsung.com>
Reviewed-by: Randeep Singh <randeep.s@samsung.com>
(cherry picked from commit 862f950c2548e138c2f2aab0678032ed8d21f4f5)
Reviewed-on: https://gerrit.iotivity.org/gerrit/5603
Tested-by: Randeep Singh <randeep.s@samsung.com>