fileSD: fix set update for getAllImages

Change-Id: I3afc389fcd02bd7b08d7b194c2e130d7541e2b9a
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=982617
Signed-off-by: Yeela Kaplan <ykaplan@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/16830
Reviewed-by: Eduardo <ewarszaw@redhat.com>