CSINodeInfo/CSIDriver controller changes

This is the 2nd PR to move CSINodeInfo/CSIDriver APIs to
v1beta1 core storage APIs. It includes controller side changes.
It depends on the PR with API changes:
https://github.com/kubernetes/kubernetes/pull/73883

pkg/volume/plugins.go

@@ -32,7 +32,6 @@ import (
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/record"
 	cloudprovider "k8s.io/cloud-provider"
-	csiclientset "k8s.io/csi-api/pkg/client/clientset/versioned"
 	"k8s.io/klog"
 	"k8s.io/kubernetes/pkg/util/mount"
 	"k8s.io/kubernetes/pkg/volume/util/recyclerclient"
@@ -318,9 +317,6 @@ type VolumeHost interface {
 	// GetKubeClient returns a client interface
 	GetKubeClient() clientset.Interface
 
-	// GetCSIClient returns a client interface to csi.storage.k8s.io
-	GetCSIClient() csiclientset.Interface
-
 	// NewWrapperMounter finds an appropriate plugin with which to handle
 	// the provided spec.  This is used to implement volume plugins which
 	// "wrap" other plugins.  For example, the "secret" volume is