FROMLIST: iommu: dma-iommu: move IOMMU/DMA-mapping code from ARM64 arch to drivers

FROMLIST: iommu: dma-iommu: move IOMMU/DMA-mapping code from ARM64 arch to drivers

This patch moves all the IOMMU-based DMA-mapping code from arch/arm64/mm
to drivers/iommu/dma-iommu-ops.c. This way it can be easily shared with
ARM architecture, which will also use them.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Conflicts:
	arch/arm64/mm/dma-mapping.c

Change-Id: I7d56fa5e6e6ef43ae6c9c76035fcf81ee5cb7069
Signed-off-by: Simon <xxm@rock-chips.com>
Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
(am from https://patchwork.freedesktop.org/patch/74408/)