Updated openstack/openstack
Project: openstack/nova  2a9f749187f819c4e6449be831f1d060543dba85

Remove duplicate index from model

Migration 249 dropped this duplicate index, but didn't update the model
to match what happened in the migration.

Change-Id: I3f63d31a0bb6f2652f49d8505cf0c02b090de89e