pinctrl: renesas: Remove unneeded #include <linux/gpio.h>

Linus reports that some Renesas pin control sub-drivers are still
including <linux/gpio.h> instead of <linux/gpio/driver.h>.  As these
sub-drivers don't need either, the includes can just be removed.

Reported-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/578825d779b45af745cc7623c7f69d2ddeadac4b.1645605227.git.geert+renesas@glider.be