mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers

The SDHI controller on SH-Mobile SoCs requires even buffer addresses,
when used with DMA.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>