Fix setting enabled_import_methods if glance is standalone

I forgot to update devstack with the section name when I did Grenade.

Change-Id: I928072e935e7a7ec24609cdc4522c96f65d3ba3b
diff --git a/lib/glance b/lib/glance
index 5fc7a7f..3e5ebde 100644
--- a/lib/glance
+++ b/lib/glance
@@ -195,7 +195,7 @@
 
     if [[ "$GLANCE_STANDALONE" == "False" ]]; then
         # NOTE(danms): Do not advertise import methods if we are running in WSGI mode
-        iniset $GLANCE_API_CONF enabled_import_methods []
+        iniset $GLANCE_API_CONF DEFAULT enabled_import_methods []
     fi
 
     # No multiple stores for swift yet