docs/topindex.html: Remove link to wipy.io, it's no longer available.

docs/topindex.html

@@ -112,12 +112,6 @@
         <a class="biglink" href="https://github.com/micropython">MicroPython on GitHub</a><br/>
         <span class="linkdescr">contribute to the source code on GitHub</span>
       </p>
-      {% if port == "wipy" %}
-        <p class="biglink">
-          <a class="biglink" href="http://wipy.io">The WiPy homepage</a><br/>
-          <span class="linkdescr">the official WiPy site</span>
-        </p>
-      {% endif %}
     </td>
   </tr></table>