Doxm payload conversion from JSON to CBOR

Doxm payload conversion from JSON to CBOR

- Updates return type to OCStackResult and parameters as part of the conversion function.
- Changes in ownership transfer to return uint8_t instead of chari for payload conversion.
- security_internals includes function which are used in the testing.
- Unit test is updated to match the changes in conversion.

Change-Id: I088d75d67d8520e853db9b14fc802e3b31481e8b
Signed-off-by: Habib Virji <habib.virji@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/5096
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-on: https://gerrit.iotivity.org/gerrit/5797