Remove deprecated APIs from volume v2 volumes_client

In volume v2 volumes_client, the deprecated APIs (transfer related) has
been re-realized in volume v2 transfers_client. Now in Queens it will be
a good time to remove these deprecated APIs.

Change-Id: I147cf2175d51b5db97395df27ddee41bc1417b49
diff --git a/releasenotes/notes/remove-deprecated-apis-from-v2-volumes-client-3ca4a5db5fea518f.yaml b/releasenotes/notes/remove-deprecated-apis-from-v2-volumes-client-3ca4a5db5fea518f.yaml
new file mode 100644
index 0000000..c75da2e
--- /dev/null
+++ b/releasenotes/notes/remove-deprecated-apis-from-v2-volumes-client-3ca4a5db5fea518f.yaml
@@ -0,0 +1,11 @@
+---
+upgrade:
+  - |
+    Remove deprecated APIs from volume v2 volumes_client, and the deprecated
+    APIs are re-realized in volume v2 transfers_client.
+
+    * create_volume_transfer
+    * show_volume_transfer
+    * list_volume_transfers
+    * delete_volume_transfer
+    * accept_volume_transfer