Fix

initcall at 0xffffffff806c5b89: pci_iommu_init+0x0/0x53c(): returned with error code -1

Return -ENODEV instead when the IOMMU is not used.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>