[gtk-doc] Add a prereq for pkg-config in gtk-doc.m4

[Matthias Clasen <matthiasc src gnome org>]

commit 6b92c8b61a25fb57448315691159d48dc83af382
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Jun 28 11:45:04 2011 -0400

    Add a prereq for pkg-config in gtk-doc.m4
    
    Not having this was causing colord build failure, since
    the colord configure.ac uses GTK_DOC_CHECK before any other
    PKG_ macros.

 gtk-doc.m4 |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gtk-doc.m4 b/gtk-doc.m4
index 75a35b8..2b59d5d 100644
--- a/gtk-doc.m4
+++ b/gtk-doc.m4
@@ -6,6 +6,7 @@ dnl Usage:
 dnl   GTK_DOC_CHECK([minimum-gtk-doc-version])
 AC_DEFUN([GTK_DOC_CHECK],
 [
+  AC_REQUIRE([PKG_PKG_CONFIG])
   AC_BEFORE([AC_PROG_LIBTOOL],[$0])dnl setup libtool first
   AC_BEFORE([AM_PROG_LIBTOOL],[$0])dnl setup libtool first