Fix Pod watch RBAC error

Commit a987062 restricted the RBAC permissions for Pods to Get and List
operations, as these are the only ones required by the swift-operator
itself. However, Get/List operations are using an informerCache, which
itself sets up a Watch to the objects. Without the required watch
permission this throws an error in the operator log like this:

    Failed to watch *v1.Pod: unknown (get pods)

config/rbac/role.yaml

@@ -12,6 +12,7 @@ rules:
   verbs:
   - get
   - list
+  - watch
 - apiGroups:
   - ""
   resources:

controllers/swiftstorage_controller.go

@@ -83,7 +83,7 @@ type Netconfig struct {
 //+kubebuilder:rbac:groups=memcached.openstack.org,resources=memcacheds,verbs=get;list;watch;
 //+kubebuilder:rbac:groups=network.openstack.org,resources=dnsdata,verbs=get;list;watch;create;update;patch;delete
 //+kubebuilder:rbac:groups=core,resources=nodes,verbs=get;list
-//+kubebuilder:rbac:groups="",resources=pods,verbs=get;list
+//+kubebuilder:rbac:groups="",resources=pods,verbs=get;list;watch;
 
 // Reconcile is part of the main kubernetes reconciliation loop which aims to
 // move the current state of the cluster closer to the desired state.