intel-iommu: fix for IOMMU early crash

pci_dev's->sysdata is highly overloaded and currently IOMMU is broken due
to IOMMU code depending on this field.

This patch introduces new field in pci_dev's dev.archdata struct to hold
IOMMU specific per device IOMMU private data.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-x86/device.h b/include/asm-x86/device.h
index d9ee5e5..87a7153 100644
--- a/include/asm-x86/device.h
+++ b/include/asm-x86/device.h
@@ -5,6 +5,9 @@
 #ifdef CONFIG_ACPI
 	void	*acpi_handle;
 #endif
+#ifdef CONFIG_DMAR
+	void *iommu; /* hook for IOMMU specific extension */
+#endif
 };
 
 #endif /* _ASM_X86_DEVICE_H */