fix the essex port of Support-DB-auto-create-suppression.patch
    
    cfg.py in the glance essex branch doesn't support __contains__,
    i.e. the 'in' keyword and so glance-manage db_sync fails.
    Duplicate option registration is ignored within cfg.py
    anyway so remove this redundant code.
    
    (cherry picked from commit 04df8e76855f4112cf824817017ca3512466fc8e)
    
    Conflicts:
    
    	openstack-glance.spec