Use asm/generic-hardirq.h to build asm/hardirq.h and also remove the unused
idle_timestamp field in irq_cpustat whilst we're at it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>