Merge branch 'irq/for-xen' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip into HEAD

* 'irq/for-xen' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Add IRQF_FORCE_RESUME