Lookup pod by owner instead of label

Lookup pod by owner instead of label

Currently, CNF is represented by deployment. It means that one CNF is
one deployment with special label name `SdewanPurpose`. We use
"Deployment" + "label" to identify a CNF.
To apply rules for CNF, we first need to find out the pods and then
extract the its IP address. It makes more sense to find pod by its owner
deployment/replicaset, than using the label match. Because the pod label
may not be the same with the deployment.

Signed-off-by: chengli3 <cheng1.li@intel.com>
Change-Id: I4174e502c7d50d48f47d61622380e57922b5cf32