CLOUDSTACK-4520: [upgrade][vmware]ExtractVolumeCmd fails with NPE while

attempting to download a volume.(cherry picked from commit 13d9070d5e)

Signed-off-by: animesh <animesh@apache.org>

engine/schema/src/com/cloud/storage/VolumeVO.java

@@ -238,6 +238,7 @@ public class VolumeVO implements Volume {
         this.chainInfo = that.getChainInfo();
         this.templateId = that.getTemplateId();
         this.deviceId = that.getDeviceId();
+        this.format = that.getFormat();
         this.uuid = UUID.randomUUID().toString();
     }