uboot-imx

i.MX28: Do data transfers via DMA in MMC driver

This utilizes the newly introduced bounce buffers in the MMC layer.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Andy Fleming <afleming@gmail.com>
Cc: Fabio Estevam <festevam@gmail.com>