posix: pthread: replace irq_lock with spinlock

We shouldn't use swapping with an interrupt lock held
as it works incorrectly on SMP platforms.

Fix that by replacing irq_lock with spinlock for pthread
subsystem.

NOTE: we fix that in a simple way with single spinlock
for mutex / cond_var / barrier. That could be improved
later (i.e. split it for several spinlocks).

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>