rbd: read configuration from the configmap

if the kms encryption configmap is not mounted
as a volume to the CSI pods, add the code to
read the configuration from the kubernetes. Later
the code to fetch the configmap will be moved to
the new sidecar which is will talk to respective
CO to fetch the encryption configurations.

The k8s configmap uses the standard vault spefic
names to add the configurations. this will be converted
back to the CSI configurations.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

deploy/rbd/kubernetes/csi-rbdplugin-provisioner.yaml

@@ -133,6 +133,12 @@ spec:
               valueFrom:
                 fieldRef:
                   fieldPath: spec.nodeName
+            # - name: POD_NAMESPACE
+            #   valueFrom:
+            #     fieldRef:
+            #       fieldPath: spec.namespace
+            # - name: KMS_CONFIGMAP_NAME
+            #   value: encryptionConfig
             - name: CSI_ENDPOINT
               value: unix:///csi/csi-provisioner.sock
           imagePullPolicy: "IfNotPresent"