iommu: Introduce new 'struct iommu_device'

This struct represents one hardware iommu in the iommu core
code. For now it only has the iommu-ops associated with it,
but that will be extended soon.

The register/unregister interface is also added, as well as
making use of it in the Intel and AMD IOMMU drivers.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 6799cf9..b7ccfb2 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -94,6 +94,8 @@
  * out of it.
  */
 
+extern const struct iommu_ops amd_iommu_ops;
+
 /*
  * structure describing one IOMMU in the ACPI table. Typically followed by one
  * or more ivhd_entrys.
@@ -1639,6 +1641,9 @@ static int iommu_init_pci(struct amd_iommu *iommu)
 					       amd_iommu_groups, "ivhd%d",
 					       iommu->index);
 
+	iommu_device_set_ops(&iommu->iommu, &amd_iommu_ops);
+	iommu_device_register(&iommu->iommu);
+
 	return pci_enable_device(iommu->dev);
 }