pinctrl: berlin: Make berlin pinctrl driver visible if COMPILE_TEST=y

It is good to allow berlin pinctrl driver to build with COMPILE_TEST, so
make the it menu visible when compile-testing.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>