IOMMU Fixes for Linux v4.2-rc0 Four fixes have queued up to fix regressions introduced after v4.1: * Don't fail IOMMU driver initialization when the add_device call-back returns -ENODEV, as that just means that the device is not translated by the IOMMU. This is pretty common on ARM. * Two fixes for the ARM-SMMU driver for a wrong feature check and to remove a redundant NULL check. * A fix for the AMD IOMMU driver to fix a boot panic on systems where the BIOS requests Unity Mappings in the IVRS table.