server: fix npe during start vr edge case (apache#10366)

DeploymentPlanner.addPod takes long value while
VmInstanceVO.getPodIdToDeployIn returns a Long value which can be null
when the VM is never started.

Signed-off-by: Abhishek Kumar <abhishek.mrt22@gmail.com>

Author: shwstppr

server/src/main/java/com/cloud/network/router/NetworkHelperImpl.java

@@ -446,7 +446,9 @@ public DomainRouterVO startVirtualRouter(final DomainRouterVO router, final User
         final int retryIndex = 5;
         final ExcludeList[] avoids = new ExcludeList[5];
         avoids[0] = new ExcludeList();
-        avoids[0].addPod(routerToBeAvoid.getPodIdToDeployIn());
+        if (routerToBeAvoid.getPodIdToDeployIn() != null) {
+            avoids[0].addPod(routerToBeAvoid.getPodIdToDeployIn());
+        }
         avoids[1] = new ExcludeList();
         avoids[1].addCluster(_hostDao.findById(routerToBeAvoid.getHostId()).getClusterId());
         avoids[2] = new ExcludeList();