PCI_GET_DN() doesnt check to see if ->sysdata has been initialised
correctly - we should instead use pci_device_to_OF_node.  Leave
PCI_GET_DN() in the one performance critical case (iommu table lookup in
pci DMA functions).  In this case ->sysdata is guaranteed to have been
initialised by the iommu setup code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>