plugins: fix memory leaks with respect to items in GListStore

This was probably missed by accident in eda460ac where oFono's origin
did get the g_autoptr treatment.

plugins/dummy/calls-dummy-provider.c

@@ -154,7 +154,9 @@ void
 calls_dummy_provider_add_origin (CallsDummyProvider *self,
                                  const gchar        *name)
 {
-  CallsDummyOrigin *origin = calls_dummy_origin_new (name);
+  g_autoptr (CallsDummyOrigin) origin = NULL;
+
+  origin = calls_dummy_origin_new (name);
   g_list_store_append (self->origins, origin);
 }
 

plugins/mm/calls-mm-provider.c

@@ -122,7 +122,7 @@ add_origin (CallsMMProvider *self,
             GDBusObject     *object)
 {
   MMObject *mm_obj;
-  CallsMMOrigin *origin;
+  g_autoptr (CallsMMOrigin) origin = NULL;
   const gchar *path;
 
   mm_obj = MM_OBJECT (object);