1. As __nmk_dir already ends with a slash, there's no need
   for an extra one.

2. No need to include macro.mk into criu/Makefile -- nothing it defines
   is used from there.

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>