[libstdc++,doc] doc/xml/manual/profile_mode.xml: Update a paper reference

[Gerald Pfeifer]

Not there yet, but getting close...

Applied.

Gerald

2017-02-10  Gerald Pfeifer  <gerald@pfeifer.com> 

	* doc/xml/manual/profile_mode.xml: Update a paper reference. 

Index: doc/xml/manual/profile_mode.xml
===================================================================
--- doc/xml/manual/profile_mode.xml	(revision 245348)
+++ doc/xml/manual/profile_mode.xml	(working copy)
@@ -328,7 +328,7 @@
 
   <para>
   For details, see
-   <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://dx.doi.org/10.1109/CGO.2009.36">paper presented at
+   <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://ieeexplore.ieee.org/document/4907670/">paper presented at
    CGO 2009</link>.
   </para>
 </section>