uboot-phytec

mmc: uniphier: Factor out FIFO accessors

Add macros to generate the FIFO accessors, since the code is almost
the same with only minor differences. This is done in preparation
for adding 16bit variant of the IP.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>