dma-mapping-fast: Add support for dma operations with sg_table

Reuse functionality for reorganizing a sg_table based on
iommu granularity and device dma segment size from dma-iommu.c.

Port dma_sync_sg_for_* from arm64.

Change-Id: I87a7f917a39feff4f201340bbf1b5c2b4c6d9101
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>