x86: Switch apm to unlocked_kernel

This pushes the lock a fair way down and the final kill looks like it
should be an easy project for someone who wants to have a shot at it.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>