atomic_spinlock_t will be used to annotate locks which are not
converted to sleeping spinlocks on preempt-rt.

rq->lock must be converted right away as rq->lock is handled by a few
raw lock operations.

Fix also the plist implementation so debugging can handle both
spinlocks and atomic_spinlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>