[gom] build-sys: Stop using INCLUDES

[Bastien Nocera <hadess src gnome org>]

commit 0bf1a9813ac474942eb4c9e6707688ba1c5035bd
Author: Christophe Fergeau <cfergeau redhat com>
Date:   Tue Feb 17 16:32:38 2015 +0100

    build-sys: Stop using INCLUDES
    
    This is deprecated in favour of CPPFLAGS and causes warnings with newer
    automake versions:
    doc/Makefile.am:31: warning: 'INCLUDES' is the old name for 'AM_CPPFLAGS' (or '*_CPPFLAGS')
    
    https://bugzilla.gnome.org/show_bug.cgi?id=740948

 doc/Makefile.am |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/doc/Makefile.am b/doc/Makefile.am
index 8a88859..d18c578 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -26,9 +26,9 @@ CFILE_GLOB=$(top_srcdir)/gom/*.c
 # Header files to ignore when scanning
 IGNORE_HFILES=gom.h
 
-# CFLAGS and LDFLAGS for compiling scan program. Only needed
+# CPPFLAGS and LDFLAGS for compiling scan program. Only needed
 # if $(DOC_MODULE).types is non-empty.
-INCLUDES = \
+GTKDOC_CPPFLAGS = \
        -I$(top_srcdir)         \
        $(GOBJECT_CFLAGS)