spinlock used in irq handler should be initialized before registering
irq, even if we know that our device has interrupts disabled; handler
is registered shared and taking spinlock is done unconditionally.  As
it is, we can and do get oopsen on boot for some configuration, depending
on irq routing - I've got a reproducer.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Ben Collins <bcollins@debian.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>