[gxml] fixed Makefile generation on debian

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 2129ad9c841abc9da3ce62bbd34dcd79a6743fa1
Author: Daniel Espinosa <esodan gmail com>
Date:   Fri Nov 6 11:16:20 2015 -0600

    fixed Makefile generation on debian

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 979e8bc..41561a4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -307,6 +307,7 @@ examples/js/Makefile
 examples/python/Makefile
 examples/vala/Makefile
 po/Makefile.in
+debian/Makefile
 debian/control
 debian/copyright
 ])