hwmon: (pmbus/ucd9000) Fix error in ucd9000_gpio_set

hwmon: (pmbus/ucd9000) Fix error in ucd9000_gpio_set

The GPIO output functionality does not work as intended.

The ucd9000_gpio_set function should set UCD9000_GPIO_CONFIG_OUT_VALUE
(bit 2) in order to change the output value of the selected GPIO.
Instead UCD9000_GPIO_CONFIG_STATUS (bit 3) is set, but this is a
read-only value. This patch fixes the mistake and provides the intended
functionality of the GPIOs.

See UCD90xxx Sequencer and System Health Controller PMBus Command SLVU352C
section 10.43 for reference.

Signed-off-by: Torben Nielsen <t8927095@gmail.com>
Link: https://lore.kernel.org/r/20250718093644.356085-2-t8927095@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>