libxrdp: channels, respect xrdp.ini channel blocking also for data

coming in from chansrv

xrdp/xrdp_mm.c

@@ -739,10 +739,13 @@ xrdp_mm_trans_process_channel_data(struct xrdp_mm *self, struct trans *trans)
     rv = xrdp_mm_trans_send_channel_data_response(self, trans);
 
     if (rv == 0)
+    {
+        if (is_channel_allowed(self->wm, chan_id))
         {
             rv = libxrdp_send_to_channel(self->wm->session, chan_id, s->p, size, total_size,
                                          chan_flags);
         }
+    }
 
     return rv;
 }