caipserver now reports correctly whether a received message is multicast.

caipserver now reports correctly whether a received message is multicast.

It uses IP_PKTINFO to determine the address used to send the message.
Resolves JIRA 589 P1.

Change-Id: Ia9d9f271421fe232ad4939e23cccf715ed30ab90
Signed-off-by: John Light <john.j.light@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/3293
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Patrick Lankswert <patrick.lankswert@intel.com>
(cherry picked from commit 0595dc899f90f76f6ef7df6684b8664bf5ee9700)
Reviewed-on: https://gerrit.iotivity.org/gerrit/3419