[timer][debug] Fix bad check in debug_check_tasks_lists()
[timer][debug] Fix bad check in debug_check_tasks_lists()

The function was checking whether there are any tasks in the sleeping list
which have state != sleeping, but it was doing it wrong because #IRQ1 could
change the state of a given task while the check in #IRQ0 has running: at
that point, the check would belive it failed, while in reality the task
has been already (safely) removed from that list, while changing its state.

vvaltchev/experimentOs,vvaltchev/experimentOs,vvaltchev/experimentOs,vvaltchev/experimentOs