Repeat definition blacklist
Repeat definition blacklist

The variable black_list is set, used, and then again set to its previous
value which is redundant.

Change-Id: I24029148f8538207cd734cdc01c992aeadc1c922

zhangg/trove,openstack/trove,openstack/trove,hplustree/trove,hplustree/trove,zhangg/trove