spacemanager: Add missing rollback in liquibase

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Acked-by: Dmitry Litvtinsev <litvinse@fnal.gov>
Patch: http://rb.dcache.org/r/6392/