Ensure devicelist access model is configured before updating it

src/xmpp/omemo.h

@@ -38,6 +38,7 @@
 #include "xmpp/iq.h"
 
 void omemo_devicelist_subscribe(void);
+void omemo_devicelist_configure_and_request(void);
 void omemo_devicelist_publish(GList* device_list);
 void omemo_devicelist_request(const char* const jid);
 void omemo_bundle_publish(gboolean first);