mmc: add DMA support to tmio_mmc driver, when used on SuperH

SDHI controllers on SuperH, served by the tmio_mmc driver, can use slave DMA
for data transfer. This patch adds support for the dmaengine API to the
tmio_mmc driver.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Ian Molton <ian@mnementh.co.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --cc drivers/mfd/Kconfig
Simple merge

diff --cc drivers/mmc/host/tmio_mmc.c
Simple merge

diff --cc drivers/mmc/host/tmio_mmc.h
Simple merge