gpio: cs5535: Simplify dependencies

The bus and architecture dependencies are already on MFD_CS5535, so
there is no need to repeat them here.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>