CLOUDSTACK-6476: Basic Zone with Multiple Pods Setup: DHCP server doesnt get deployed in the pod where the VM gets deployed

Changes:
PodId in which the router should get started was not being saved to the DB due to the VO's setter method not following the setXXX format. So when planner loaded the router from DB, it always got podId as null and that would allow planner to deploy the router in any pod. If the router happens to start in a different pod than the user VM, the Vm fails to start since the Dhcp service check fails.

Fixed the VO's setPodId method, that was causing the DB save operation fail.