Enable configuring mountOptions, reclaimPolicy and volumeBindingMode … (#10450)

* Enable configuring mountOptions, reclaimPolicy and volumeBindingMode for cinder-csi StorageClasses

* Check if class.mount_options is defined at all, before generating the option list

inventory/sample/group_vars/all/openstack.yml

@@ -48,3 +48,13 @@
 ## Make sure to source in the openstack credentials
 # cinder_csi_enabled: true
 # cinder_csi_controller_replicas: 1
+# storage_classes:
+#   - name: "cinder-csi"
+#     provisioner: "kubernetes.io/cinder"
+#     mount_options:
+#       - "discard"
+#     parameters:
+#       type: "thin"
+#       availability: "nova"
+#     reclaim_policy: "Delete"
+#     volume_binding_mode: "WaitForFirstConsumer"