[gom] build: Use "subdir-objects" for newer autotools

[Bastien Nocera <hadess src gnome org>]

commit 03f516d729dff0a557408dcebf1945c04e0d3feb
Author: Joseph Herlant <herlantj gmail com>
Date:   Fri Jan 2 02:14:14 2015 +0000

    build: Use "subdir-objects" for newer autotools
    
    This avoids a warning with newer versions of the autotools
    
    https://bugzilla.gnome.org/show_bug.cgi?id=740948

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index a45f4e0..1e1d8d7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -23,7 +23,7 @@ AC_INIT([gom],[gom_version])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([m4])
 
-AM_INIT_AUTOMAKE([-Wno-portability no-dist-gzip dist-xz])
+AM_INIT_AUTOMAKE([-Wno-portability no-dist-gzip dist-xz subdir-objects])
 
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 AS_AM_REALLY_SILENT