Make use of DMA to transfer multiple blocks at one time. It could
improve the performance on MMC/SD driver.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>