Implement missing unit tests for CKM.

Implement missing unit tests for CKM.

Added CKM unit tests to common build.
Added result state to functions.
Change-Id: I11ef2d003f95d850ed395f5c2584bbb34ca154a4
Signed-off-by: i.pazderskyy <i.pazderskyy@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/8307
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Dmitriy Zhuravlev <d.zhuravlev@samsung.com>
Reviewed-by: Chul Lee <chuls.lee@samsung.com>
Reviewed-by: Jongsung Lee <js126.lee@samsung.com>
Reviewed-by: Randeep Singh <randeep.s@samsung.com>