[yelp-xsl] configure.ac: Only check for xmllint/xsltproc when needed

[Shaun McCance <shaunm src gnome org>]

commit 167f4ce3cee68b1c504b2dbc14c6b53bcf002a28
Author: Shaun McCance <shaunm gnome org>
Date:   Sun Nov 3 12:59:05 2013 -0500

    configure.ac: Only check for xmllint/xsltproc when needed
    
    Fixes https://bugzilla.gnome.org/show_bug.cgi?id=700670
    
    Also dropped AC_ARG_VAR on itstool, because we weren't using
    it anyway.

 configure.ac |   19 +++++++++++--------
 1 files changed, 11 insertions(+), 8 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3a375b6..0addcf7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -17,7 +17,6 @@ else
 fi
 AC_SUBST(YELP_XSL_AWK)
 
-AC_ARG_VAR([ITSTOOL], [Path to the `itstool` command])
 AC_CHECK_PROG([ITSTOOL], [itstool], [itstool])
 if test x"$ITSTOOL" = x; then
   AC_MSG_ERROR([itstool is required to build the translation XML files])
@@ -27,13 +26,6 @@ if test "$ITSTOOL_VERSION" -lt 10200; then
   AC_MSG_ERROR([itstool >= 1.2.0 is required to build the translation XML files])
 fi
 
-# Dependecies
-PKG_CHECK_MODULES(YELP_XSL,
-[
-       libxml-2.0 >= 2.6.12
-       libxslt    >= 1.1.8
-])
-
 # i18n stuff
 GETTEXT_PACKAGE=yelp-xsl
 AC_SUBST(GETTEXT_PACKAGE)
@@ -49,6 +41,17 @@ AC_ARG_ENABLE(doc,
               enable_doc=no)
 AM_CONDITIONAL(ENABLE_DOC, test "x$enable_doc" != "xno")
 
+AS_IF([test "x$enable_doc" != "xno"],[
+AC_CHECK_PROG(XMLLINT, xmllint, xmllint)
+if test x"$XMLLINT" = x; then
+  AC_MSG_ERROR([xmllint not found])
+fi
+AC_CHECK_PROG(XSLTPROC, xsltproc, xsltproc)
+if test x"$XSLTPROC" = x; then
+  AC_MSG_ERROR([xsltproc not found])
+fi
+])
+
 AC_CONFIG_FILES([
 Makefile
 yelp-xsl.pc