Fix for C2036 void pointer unknown size build error on Windows.

channels/rail/rail_main.c

@@ -128,7 +128,7 @@ static void rail_recv_set_sysparams_event(rdpRailOrder* rail_order, RDP_EVENT* e
 	while (data && data->size > 0)
 	{
 		rail_process_plugin_data(rail_order, data);
-		data = (RDP_PLUGIN_DATA*)(((void*) data) + data->size);
+		data = (RDP_PLUGIN_DATA*)((char *)(data) + data->size);
 	}
 }