Sched: Do not try to run frozen jobs.
Sched: Do not try to run frozen jobs.

Calling frozen() from outside the job is enough, if woken up the job will just
check frozen() and yield immediately.

	* lib/sched/scheduler.cc (execute_round): Do not switch to a frozen job.

aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport