docs: update documentation for volume clone

after cross-storageclass clone/restore, now we can
clone across different storageclass.
this commit updates the documentation indicating
the same.

Signed-off-by: yati1998 <ypadia@redhat.com>

Documentation/Storage-Configuration/Ceph-CSI/ceph-csi-volume-clone.md

@@ -17,8 +17,12 @@ for more info.
 
 In [pvc-clone](https://github.com/rook/rook/tree/master/deploy/examples/csi/rbd/pvc-clone.yaml),
 `dataSource` should be the name of the `PVC` which is already created by RBD
-CSI driver. The `dataSource` kind should be the `PersistentVolumeClaim` and also storageclass
-should be same as the source `PVC`.
+CSI driver. The `dataSource` kind should be the `PersistentVolumeClaim`.
+The `storageClassName` can be any storageclass (not necessarily same as Parent PVC) with the
+following conditions:
+
+* `provisinor` should be same for both the Parent PVC and the Clone PVC.
+* The non-encrypted PVC cannot be cloned to an encrypted one and vise-versa.
 
 Create a new PVC Clone from the PVC
 
@@ -55,8 +59,11 @@ kubectl delete -f deploy/examples/csi/rbd/pvc-clone.yaml
 
 In [pvc-clone](https://github.com/rook/rook/tree/master/deploy/examples/csi/cephfs/pvc-clone.yaml),
 `dataSource` should be the name of the `PVC` which is already created by CephFS
-CSI driver. The `dataSource` kind should be the `PersistentVolumeClaim` and also storageclass
-should be same as the source `PVC`.
+CSI driver. The `dataSource` kind should be the `PersistentVolumeClaim`.
+The `storageClassName` can be any storageclass (not necessarily same as Parent PVC) with the
+following conditions:
+
+* `provisinor` should be same for both the Parent PVC and the Clone PVC.
 
 Create a new PVC Clone from the PVC