mmc: Convert HI6220 MMC driver to driver model

Convert HiSilicon HI6220 MMC driver based on DWMMC IP to driver
model.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: Enable this on poplar]
Signed-off-by: Tom Rini <trini@konsulko.com>
3 files changed