hwmon: (adt7475) Fix sysfs file names

The adt7475 driver creates pwm#_auto_channel_temp attributes instead
of the standard pwm#_auto_channels_temp. Fix it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>