[glibmm] Build: Fix silent builds

[Sebastian Geiger <segeiger src gnome org>]

commit b46a1362c5f09ec4244abce814832faacaec3091
Author: Sebastian Geiger <sbastig gmx net>
Date:   Thu Jul 14 10:58:07 2016 +0200

    Build: Fix silent builds
    
    Silent builds were introduced in commit
    fa03634b5963af18340258a67063f3a527c4e471
    but they were not really enabled. Passing
    yes to AM_SILENT_RULES fixes this issue.
    
    See https://wiki.gnome.org/Initiatives/GnomeGoals/NicerBuilds
    for more information.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=768797

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 76cad4b..6d1bfd3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,7 @@ AC_CONFIG_MACRO_DIR([build])
 AC_CONFIG_HEADERS([config.h glib/glibmmconfig.h gio/giommconfig.h])
 
 AM_INIT_AUTOMAKE([1.9 -Wno-portability no-dist-gzip dist-xz tar-ustar no-define nostdinc])
-m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES])
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 AM_MAINTAINER_MODE
 AC_ARG_VAR([ACLOCAL_FLAGS], [aclocal flags, e.g. -I <macro dir>])