acinclude.m4 (GLIBCXX_CONFIGURE_DOCBOOK): Also check for /usr/share/xml/docbook/stylesheet/nwalsh5/current.

* acinclude.m4 (GLIBCXX_CONFIGURE_DOCBOOK): Also check for
/usr/share/xml/docbook/stylesheet/nwalsh5/current.
* configure: Regenerate.

From-SVN: r193413