[PATCH,libstdc++] Update link to "Why not LGPL".

[Gerald Pfeifer]

Committed.  With a one line GIT log at the top. ;-)

Gerald


2019-11-11  Gerald Pfeifer  <gerald@pfeifer.com>

	* doc/xml/gnu/gpl-3.0.xml: Adjust link to "Why not LGPL".

Index: doc/xml/gnu/gpl-3.0.xml
===================================================================
--- doc/xml/gnu/gpl-3.0.xml	(revision 278050)
+++ doc/xml/gnu/gpl-3.0.xml	(working copy)
@@ -829,6 +829,6 @@ under certain conditions; type Β‘<literal>show c<
     subroutine library, you may consider it more useful to permit linking
     proprietary applications with the library.  If this is what you want to do,
     use the <acronym>GNU</acronym> Lesser General Public License instead of this
-    License.  But first, please read <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://www.gnu.org/philosophy/why-not-lgpl.html">https://www.gnu.org/philosophy/why-not-lgpl.html</link>.
+    License.  But first, please read <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://www.gnu.org/licenses/why-not-lgpl.html">https://www.gnu.org/licenses/why-not-lgpl.html</link>.
   </para>
 </appendix>