uniphier: make eMMC controller base address configurable

The next SoC supports the same eMMC controller, but the register
base will be changed. Make it configurable.

Change-Id: I00cb5531bc3d8d49357ad5e922cdd3d785355edf
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
3 files changed