feat(HA): adding support to have controller in HA

We can have more than one controller in the system, but only one will
be the master and others will be slave. Once master is down, one of the slave will
take over via lease mechanism and start provisioning/deprovisioning the volumes.

Signed-off-by: Pawan <pawan@mayadata.io>

deploy/zfs-operator.yaml

@@ -82,6 +82,9 @@ rules:
   - apiGroups: [""]
     resources: ["events"]
     verbs: ["list", "watch", "create", "update", "patch"]
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "watch", "list", "delete", "update", "create"]
   - apiGroups: ["*"]
     resources: ["zfsvolumes"]
     verbs: ["*"]
@@ -112,7 +115,7 @@ spec:
       app: openebs-zfs-controller
       role: openebs-zfs
   serviceName: "openebs-zfs"
-  replicas: 1
+  replicas: 2
   template:
     metadata:
       labels:
@@ -130,6 +133,8 @@ spec:
             - "--v=5"
             - "--feature-gates=Topology=true"
             - "--strict-topology"
+            - "--enable-leader-election"
+            - "--leader-election-type=leases"
           env:
             - name: ADDRESS
               value: /var/lib/csi/sockets/pluginproxy/csi.sock
@@ -142,6 +147,7 @@ spec:
           args:
             - "--v=5"
             - "--csi-address=$(ADDRESS)"
+            - "--leader-election"
           env:
             - name: ADDRESS
               value: /var/lib/csi/sockets/pluginproxy/csi.sock
@@ -201,7 +207,9 @@ rules:
   - apiGroups: ["storage.k8s.io"]
     resources: ["volumeattachments", "csinodes"]
     verbs: ["get", "list", "watch", "update", "patch"]
-
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "watch", "list", "delete", "update", "create"]
 ---
 kind: ClusterRoleBinding
 apiVersion: rbac.authorization.k8s.io/v1