[wwwdocs] Remove dead Caldera link

[Joseph S. Myers]

On Sun, 7 Mar 2010, Gerald Pfeifer wrote:

> -  <li><a href="http://www.caldera.com/developers/gabi/">The System V Application Binary Interface</a>, aka the ELF Generic ABI Specification.</li>
> -

After several years of not being updated,
http://www.sco.com/developers/gabi/latest/contents.html
does now seem to get new e_machine values added reasonably promptly after 
registration.

-- 
Joseph S. Myers
joseph@codesourcery.com