x64, x2apic/intr-remap: Interrupt remapping infrastructure

Interrupt remapping (part of Intel Virtualization Tech for directed I/O)
infrastructure.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/pci/intr_remapping.h b/drivers/pci/intr_remapping.h
index c4a40b2..05f2635 100644
--- a/drivers/pci/intr_remapping.h
+++ b/drivers/pci/intr_remapping.h
@@ -4,3 +4,5 @@
 	struct intel_iommu *iommu;
 	unsigned int id;
 };
+
+#define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0)