Security code comments which are doxygen compliant

Security code comments which are doxygen compliant

Some file using comments similar to doxygen changed.
Comments has been updated to used return instead of retval.
Comments having in/out tags has been updated.
Some functions missing space after keyword has been updated.

Change-Id: I0e9b75d2f75576f992d0ff4bafeaf5ba16917cc6
Signed-off-by: Habib Virji <habib.virji@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/5027
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Jon A. Cruz <jonc@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/5757