[glib] configure: test have_docbook_style != yes, not have_docbook_dtd

[Alexander Larsson <alexl src gnome org>]

commit f5d4543139172f366afa0de36dd7e5eac08e2297
Author: Alexander Larsson <alexl redhat com>
Date:   Wed Jun 17 17:31:19 2015 +0200

    configure: test have_docbook_style != yes, not have_docbook_dtd

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index b297fc4..60423e4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2603,7 +2603,7 @@ AS_IF([test "$enable_man" != no], [
   dnl check for DocBook XSL stylesheets in the local catalog
   JH_CHECK_XML_CATALOG([http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl],
      [DocBook XSL Stylesheets], [have_docbook_style=yes],[have_docbook_style=no])
-  AS_IF([ test "$have_docbook_dtd" != yes ], [
+  AS_IF([ test "$have_docbook_style" != yes ], [
     AS_IF([ test "$enable_man" = yes ], [
       AC_MSG_ERROR([DocBook XSL Stylesheets are required for --enable-man])
     ])