[wwwdocs] Remove stale link to "Guide for the use of the Ada programming language in high integrity systems"

[Gerald Pfeifer]

Installed.

Gerald

Index: readings.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/readings.html,v
retrieving revision 1.183
diff -u -3 -p -r1.183 readings.html
--- readings.html	7 Oct 2008 00:05:03 -0000	1.183
+++ readings.html	25 Oct 2008 16:57:21 -0000
@@ -562,9 +562,6 @@ Intel®64 and IA-32 Architectures Sof
    The GNU Ada Compiler</a></li>
    <li><a href="http://www.adaic.org/docs/95style/html/cover.html">Ada
    Quality & Style Guide</a></li>
-   <li><a href="http://polaris.dit.upm.es/~ork/documents/adahis.pdf">Guide
-   for the use of the Ada programming language in high integrity
-    systems</a></li>
    <li><a href="http://www.sigada.org/ada_letters/jun2004/ravenscar_article.pdf">Guide
    for the use of the Ada Ravenscar Profile in high integrity
    systems</a></li>