Pul IOMMU fixes from Joerg Roedel:
 "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"

* tag 'iommu-fixes-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Introduce protection_domain_init() function
  iommu/arm-smmu: Delete an unnecessary check before the function call "free_io_pgtable_ops"
  iommu/arm-smmu: Fix broken ATOS check
  iommu: Ignore -ENODEV errors from add_device call-back