ARM: shmobile: ape6evm: add DMA support to MMCIF

Add DMA support for MMCIF on APE6EVM, using the shdma dmaengine driver.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>