[gnome-power-manager] Enable pretty compiler output with new automake versions

[Richard Hughes <rhughes src gnome org>]

commit 7e1f20000206f2795ae0bb6943d1bdfe3b1a6c54
Author: Richard Hughes <richard hughsie com>
Date:   Wed Jul 1 20:58:06 2009 +0100

    Enable pretty compiler output with new automake versions

 configure.ac |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3abcc8e..3400523 100644
--- a/configure.ac
+++ b/configure.ac
@@ -7,6 +7,9 @@ AM_INIT_AUTOMAKE([foreign])
 AM_CONFIG_HEADER(config.h)
 AC_CONFIG_MACRO_DIR([m4])
 
+# enable nice build output on automake1.11
+m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
+
 AC_PROG_CC
 AM_PROG_CC_C_O