[wwwdocs] Adjust 2015 ACM Award link

[Gerald Pfeifer]

Applied.

Gerald

Index: index.html
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RCS file: /cvs/gcc/wwwdocs/htdocs/index.html,v
retrieving revision 1.1047
diff -u -r1.1047 index.html
--- index.html	15 Mar 2017 14:31:25 -0000	1.1047
+++ index.html	11 Apr 2017 22:10:19 -0000
@@ -85,7 +85,7 @@
     <span class="date">[2016-06-03]</span></dt>
     <dd></dd>
 
-<dt><span><a href="http://www.acm.org/awards/2015-technical-awards">2015 ACM Software System Award</a></span>
+<dt><span><a href="http://awards.acm.org/about/2015-technical-awards">2015 ACM Software System Award</a></span>
     <span class="date">[2016-04-29]</span></dt>
     <dd></dd>