gpio: madera: Add support for Cirrus Logic CS47L92

As the gpio is common to all madera codecs all that is needed
is to setup the correct number of GPIO pins for the CS47L92.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20190722090748.20807-4-ckeepax@opensource.cirrus.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>