tools: rinaperf: implement stoppable_usleep() to avoid ^C delays
tools: rinaperf: implement stoppable_usleep() to avoid ^C delays

autrimpo/rlite,autrimpo/rlite,vmaffione/rlite,autrimpo/rlite,autrimpo/rlite,vmaffione/rlite,vmaffione/rlite,vmaffione/rlite