Commit 8d6ce64cd08c0598963a92844495782997cd59f3 started using the native
quote attribute built into sqlalchemy 0.9 but missed the changes to the
ibmdb2 changeset, so alter table statements fail for DB2 on sqlalchemy
>= 0.9 (tested against 0.9.8).
This fixes the same issue for the ibmdb2 changeset.
Change-Id: Ia3fa6c3090b5eab29ed7746f4795d502990b8a2f