This commit added kecho to scripts/Kbuild.include (and doc).
Backported just Kbuild.include part to Makefile

commit 5410ecc0def8955ab99810c5626cc7e156991896
Author: Mike Frysinger <vapier@gentoo.org>
Date:   Thu Nov 6 03:31:34 2008 -0500

    kbuild: introduce $(kecho) convenience echo

Index: kconfig/Makefile
===================================================================
--- kconfig.orig/Makefile
+++ kconfig/Makefile
@@ -6,6 +6,12 @@
 PHONY += xconfig gconfig menuconfig config syncconfig update-po-config \
 	localmodconfig localyesconfig
 
+# Easy method for doing a status message
+       kecho := :
+ quiet_kecho := echo
+silent_kecho := :
+kecho := $($(quiet)kecho)
+
 ifdef KBUILD_KCONFIG
 Kconfig := $(KBUILD_KCONFIG)
 else