Makefile.inc: Build test intelvbttool

Add intelvbttool to list of utilities to be build tested by the build
servers.

Change-Id: Id75724726778fd939fb7497f5b33a3d5d58124fd
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/12085
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
diff --git a/Makefile.inc b/Makefile.inc
index 5b8e4dc..b85a2cb 100644
--- a/Makefile.inc
+++ b/Makefile.inc
@@ -703,6 +703,7 @@
 	cbmem \
 	ectool \
 	inteltool \
+	intelvbttool \
 	nvramtool \
 	superiotool \
 	viatool