[gobject-introspection] build: Fix gtk-doc srcdir != builddir

[Colin Walters <walters src gnome org>]

commit 349fc37b29c2e2c9d15c6c53c88f4dd108a94945
Author: Colin Walters <walters verbum org>
Date:   Mon Jul 25 16:51:55 2011 -0400

    build: Fix gtk-doc srcdir != builddir
    
    gtk-doc apparently lies about the path being relative...fix it by just
    using $(srcdir).

 docs/reference/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/docs/reference/Makefile.am b/docs/reference/Makefile.am
index f645604..19c9aff 100644
--- a/docs/reference/Makefile.am
+++ b/docs/reference/Makefile.am
@@ -7,7 +7,7 @@ DOC_MODULE=gi
 DOC_MAIN_SGML_FILE=gi-docs.sgml
 
 # The directory containing the source code. Relative to $(srcdir)
-DOC_SOURCE_DIR=../../girepository
+DOC_SOURCE_DIR=$(top_srcdir)/girepository
 
 # Extra options to supply to gtkdoc-scan
 SCAN_OPTIONS=