huawei: avoid trying to disable parent voice unsolicited events

Which actually segfaults, as MMBroadbandModem doesn't implement the
disable_unsolicited_events() method in the voice interface.

plugins/huawei/mm-broadband-modem-huawei.c

@@ -3204,19 +3204,19 @@ static const MMBaseModemAtCommand unsolicited_voice_disable_sequence[] = {
 };
 
 static void
-parent_voice_disable_unsolicited_events_ready (MMIfaceModemVoice *self,
+modem_voice_disable_unsolicited_events (MMIfaceModemVoice *self,
-                                               GAsyncResult *res,
+                                        GAsyncReadyCallback callback,
-                                               GSimpleAsyncResult *simple)
+                                        gpointer user_data)
 {
-    GError *error = NULL;
+    GSimpleAsyncResult *simple;
 
-    if (!iface_modem_voice_parent->disable_unsolicited_events_finish (self, res, &error)) {
+    simple = g_simple_async_result_new (G_OBJECT (self),
-        g_simple_async_result_take_error (simple, error);
+                                        callback,
-        g_simple_async_result_complete (simple);
+                                        user_data,
-        g_object_unref (simple);
+                                        modem_voice_disable_unsolicited_events);
-    }
+
+    /* No unsolicited events disabling in parent */
 
-    /* Our own enable now */
     mm_base_modem_at_sequence_full (
         MM_BASE_MODEM (self),
         mm_base_modem_peek_port_primary (MM_BASE_MODEM (self)),
@@ -3228,25 +3228,6 @@ parent_voice_disable_unsolicited_events_ready (MMIfaceModemVoice *self,
         simple);
 }
 
-static void
-modem_voice_disable_unsolicited_events (MMIfaceModemVoice *self,
-                                        GAsyncReadyCallback callback,
-                                        gpointer user_data)
-{
-    GSimpleAsyncResult *result;
-
-    result = g_simple_async_result_new (G_OBJECT (self),
-                                        callback,
-                                        user_data,
-                                        modem_voice_disable_unsolicited_events);
-
-    /* Chain up parent's enable */
-    iface_modem_voice_parent->disable_unsolicited_events (
-        self,
-        (GAsyncReadyCallback)parent_voice_disable_unsolicited_events_ready,
-        result);
-}
-
 /*****************************************************************************/
 /* Create call (Voice interface) */