csi: add pvc & pod yamls for block volume mode

This commit adds example yamls for block
volume mode.

Signed-off-by: Rakshith R <rar@redhat.com>
(cherry picked from commit 53e2f8c)

deploy/examples/csi/rbd/raw-block-pod.yaml

@@ -0,0 +1,17 @@
+---
+apiVersion: v1
+kind: Pod
+metadata:
+  name: csirbd-block-demo-pod
+spec:
+  containers:
+    - name: centos
+      image: quay.io/centos/centos:latest
+      command: ["/bin/sleep", "infinity"]
+      volumeDevices:
+        - name: mypvc
+          devicePath: /dev/xvda
+  volumes:
+    - name: mypvc
+      persistentVolumeClaim:
+        claimName: raw-block-rbd-pvc

deploy/examples/csi/rbd/raw-block-pvc.yaml

@@ -0,0 +1,13 @@
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: raw-block-rbd-pvc
+spec:
+  accessModes:
+    - ReadWriteOnce
+  volumeMode: Block
+  resources:
+    requests:
+      storage: 1Gi
+  storageClassName: rook-ceph-block