An attempt to convert the driver to using GPIO descriptors
(see Link tag) was discouraged in favor of deleting the
handling of the update GPIO altogehter since there are
no in-tree users.

This patch deletes the GPIO handling instead.

Cc: Richard Fitzgerald <rf@opensource.cirrus.com>
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/linux-watchdog/20200210102209.289379-1-linus.walleij@linaro.org/Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20200229115046.57781-1-linus.walleij@linaro.orgSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>