arm: IOMMU: Tegra30: Add iommu_ops for SMMU driver

Tegra 30 IOMMU H/W, SMMU (System Memory Management Unit). This patch
implements struct iommu_ops for SMMU to be used in the standard IOMMU
API.

This H/W module supports multiple virtual address spaces(domain x4),
and manages 2 level H/W translation pagetable.

Change-Id: Iaad09401d3661bcfd6732934be9595283a46e652
Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Reviewed-on: http://git-master/r/72215
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Varun Wadekar <vwadekar@nvidia.com>
Reviewed-by: Krishna Reddy <vdumpa@nvidia.com>

Conflicts:
	drivers/iommu/Kconfig
	drivers/iommu/Makefile