one more fix about deletestoragepool

set uuid of storagepoolvo to null

server/src/com/cloud/storage/StorageManagerImpl.java

@@ -1314,6 +1314,8 @@ public class StorageManagerImpl implements StorageManager {
 
         // if not records exist, delete the given pool (base case)
         if (hostPoolRecords.size() == 0) {
+            sPool.setUuid(null);
+            _storagePoolDao.update(id, sPool);
             _storagePoolDao.remove(id);
             return true;
         } else {