Use "glance_registry_api" as the backend name

"glance_registry_api" is used instead of "glance-registry-api" as the backend
name in the haproxy configuration. Ideally, we should not rely on names defined
in the user configuration, but we have no solution for this right now.

Change-Id: Id4472aaf644a8c7103fa5ae660124bb75cfadc64
1 file changed