hwmon: (pmbus/core) notify on the hwmon device, not the i2c client

hwmon: (pmbus/core) notify on the hwmon device, not the i2c client

pmbus_notify() calls sysfs_notify() and kobject_uevent() on the i2c
client's kobject, but the alarm attributes live on the hwmon class
device registered by pmbus_do_probe(). Notifying the parent i2c device
is a no-op for both poll(POLLPRI) waiters and udev listeners: the named
attribute does not exist on that kobject.

Notify the hwmon device instead, so poll() wakes up and "change"
uevents fire on the inX_alarm/tempX_alarm attributes when SMBALERT#
reports a fault.

Fixes: f469bde9afd1 ("hwmon: (pmbus/core) Notify hwmon events")
Cc: stable@vger.kernel.org # v6.4+
Signed-off-by: Vincent Jardin <vjardin@free.fr>
Link: https://lore.kernel.org/r/20260723-fix_hwmon_notify_v1-v1-1-5a24c528686d@free.fr
Signed-off-by: Guenter Roeck <linux@roeck-us.net>