[gtkglext] Add GDK_CFLAGS.

[Ralf Corsépius <rcorsepius src gnome org>]

commit be6a138822cf3dcbda0f6e2df9129bac509586f5
Author: Ralf Corsepius <rcorsepius src gnome org>
Date:   Tue Dec 22 16:53:24 2009 +0100

    Add GDK_CFLAGS.

 docs/reference/gtkglext/Makefile.am |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gtkglext/Makefile.am b/docs/reference/gtkglext/Makefile.am
index 6f144be..7aec7a7 100644
--- a/docs/reference/gtkglext/Makefile.am
+++ b/docs/reference/gtkglext/Makefile.am
@@ -63,6 +63,7 @@ extra_files = \
 # CFLAGS and LDFLAGS for compiling scan program. Only needed if your app/lib
 # contains GtkObjects/GObjects and you want to document signals and properties.
 GTKDOC_CFLAGS = \
+	@GDK_CFLAGS@ \
 	@CFLAGS@			\
 	-I$(top_srcdir)			\
 	-I$(top_srcdir)/gdk		\