hwmon: (adt7475) Fix default duty on fan is disabled

[ Upstream commit 39b24cced70fdc336dbc0070f8b3bde61d8513a8 ]

According to the comments on fan is disabled, we change to manual mode
and set the duty cycle to 0.
For setting the duty cycle part, the register is wrong. Fix it.

Fixes: 1c301fc5 ("hwmon: Add a driver for the ADT7475 hardware monitoring chip")
Signed-off-by: Wayne Tung <chineweff@gmail.com>
Link: https://lore.kernel.org/r/20240701073252.317397-1-chineweff@gmail.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>