dma-mapping: add {map,unmap}_resource to dma_map_ops

Add methods to handle mapping of device resources from a physical
address. This is needed for example to be able to map MMIO FIFO
registers to a IOMMU.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>