In migrate_irqs_away we werent converting a virtual irq to a real one.  We
ended up passing the wrong irq numbers to the hypervisor and migration of
affinitised irqs on cpu hot unplug didnt work.

Also clarify the rtas_stop_self printk.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>