Grizzly to Havana Upgrade wipes out Nova quota_usages

Migration script 216 will wipe out all data in quota_usages table
when user_id is null. After the upgrade from Grizzly to Havana is
completed, the migration script 203 adds a new column user_id, so
user_id is null for all data in quota_usages. So the correct
behaviour should be sync quota_usages table first and then delete
data if user_id is still null.

Fixing the existing migrate script is because we can not find
the quota_usages data after migration script 216.

Closes-bug:1245746

Change-Id: I4db62884785a4eb6e1db2c5b114b9c6e1b4882ad