docs/docs.html: fix mailing list link

As reported on IRC.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

docs/docs.html

@@ -20,7 +20,7 @@ Current documentation for buildroot includes:
 
   <li>
     If you find that you need help with buildroot, you can ask for help on the
-    <a href= "lists/uClibc/">buildroot mailing list</a> at buildroot at mail.uclibc.org.
+    <a href= "/lists/buildroot/">buildroot mailing list</a> at buildroot at mail.uclibc.org.
     In addition the BusyBox, uClibc, and buildroot developers are also known to
     hang out on the uClibc IRC channel: #uclibc on irc.freenode.net.
   </li>