fix banner placements

contrib/templates/default/frontpage.mustache

@@ -74,10 +74,8 @@
     </div>
     </center>
     <script src="{{prefix}}static/nntpchan.js" type="text/javascript">
-      document.onload = function() {
         var e = document.getElementById("nntpchan_banner");
         nntpchan_inject_banners(e, "{{prefix}}");
-      }
     </script>
 
   </body>