Run Glance initialization when Glance is enabled, not just registry (v2)

Per [1] Glance registry should not be required to run since Queens.

v2 improves on v1 [2] (now reverted [3]) by applying minor comments
from reviews so far and ensuring nova-live-migration job does not see
a change in behavior and hence does not break [4].
[5] tried to fix the issue but it did only partially, regarding
the database but not the image upload [6].
This patch ensures double cirros image upload does not happen as well.

[1] https://specs.openstack.org/openstack/glance-specs/specs/queens/approved/glance/deprecate-registry.html
[2] https://review.opendev.org/702707
[3] https://review.opendev.org/703131
[4] https://bugs.launchpad.net/devstack/+bug/1860021
[5] https://review.opendev.org/702960
[6] https://bugs.launchpad.net/devstack/+bug/1860021/comments/16

Change-Id: I61538acd6bd4c7b3da26c4084225b220d7d1aa2c
Closes-bug: #1859847
Related-bug: #1860021
diff --git a/lib/glance b/lib/glance
index b4cab2a..740bcab 100644
--- a/lib/glance
+++ b/lib/glance
@@ -276,18 +276,16 @@
     rm -rf $GLANCE_IMAGE_DIR
     mkdir -p $GLANCE_IMAGE_DIR
 
-    if is_service_enabled $DATABASE_BACKENDS; then
-        # (Re)create glance database
-        recreate_database glance
+    # (Re)create glance database
+    recreate_database glance
 
-        time_start "dbsync"
-        # Migrate glance database
-        $GLANCE_BIN_DIR/glance-manage --config-file $GLANCE_CONF_DIR/glance-api.conf db_sync
+    time_start "dbsync"
+    # Migrate glance database
+    $GLANCE_BIN_DIR/glance-manage --config-file $GLANCE_CONF_DIR/glance-api.conf db_sync
 
-        # Load metadata definitions
-        $GLANCE_BIN_DIR/glance-manage --config-file $GLANCE_CONF_DIR/glance-api.conf db_load_metadefs
-        time_stop "dbsync"
-    fi
+    # Load metadata definitions
+    $GLANCE_BIN_DIR/glance-manage --config-file $GLANCE_CONF_DIR/glance-api.conf db_load_metadefs
+    time_stop "dbsync"
 }
 
 # install_glanceclient() - Collect source and prepare