nvmem: uniphier: change access unit from 32bit to 8bit

The efuse on UniPhier allows 8bit access according to the specification.
Since bit offset of nvmem is limited to 0-7, it is desiable to change
access unit of nvmem to 8bit.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>