Add option "nointremap" to disable interrupt remapping.

[ Impact: add new boot option ]
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Acked-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: allen.m.kay@intel.com
Cc: fenghua.yu@intel.com
LKML-Reference: <1239957736-6161-5-git-send-email-weidong.han@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>