[libgtop] Enable silent build.

[Robert Roth <robertroth src gnome org>]

commit a3a16707b58bc9d652c179dfe615f5d93ffc1540
Author: Benoit Dejean <bdejean gmail com>
Date:   Sat Feb 28 00:19:17 2015 +0100

    Enable silent build.

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 72ae368..bbdda0f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -34,6 +34,7 @@ AC_CONFIG_HEADERS(config.h)
 AC_CANONICAL_HOST
 
 AM_INIT_AUTOMAKE([-Wno-portability tar-ustar no-dist-gzip dist-xz])
+AM_SILENT_RULES([yes])
 AC_CONFIG_MACRO_DIR([m4])
 GOBJECT_INTROSPECTION_CHECK([0.6.7])