From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes request_irq() potentially called from atomic context.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>