pinctrl: uniphier: make drivers non-modular

At first these drivers were written as tristate, but the module
usecases are actually not tested.  Make all of them boolean.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>