benchmark/common: Disable set_core_affinity. Add thread_id() helper.

Signed-off-by: Michael Lippautz <michael.lippautz@gmail.com>
Add thread id based balancer to framework.

Signed-off-by: Michael Lippautz <michael.lippautz@gmail.com>
utils: Add simple spinning barrier.

Signed-off-by: Michael Lippautz <michael.lippautz@gmail.com>