pinctrl: rza1: make structures rza1_gpiochip_template and rza1_pinmux_ops static

structures rza1_gpiochip_template and rza1_pinmux_ops do not need to be
in global scope, so make them static.

Cleans up sparse warnings:
symbol 'rza1_gpiochip_template' was not declared. Should it be static?
symbol 'rza1_pinmux_ops' was not declared. Should it be static?

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>