ARM: uniphier: enable Cadence eMMC controller for LD11/LD20

Enable SDMA (Single Operation DMA) for LD11, but not for LD20.
The SDMA does not work for LD20 boards because they are generally
equipped with more memory than fits in the 32 bit physical address
space supported by the SDMA.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>