hwmon: (aspeed-pwm-tacho) Use devm_thermal_of_cooling_device_register

Use devm_thermal_of_cooling_device_register() to register the cooling
device. As a side effect, this fixes a driver bug:
thermal_cooling_device_unregister() was not called on removal.

Fixes: f198907d ("hwmon: (aspeed-pwm-tacho) cooling device support.")
Cc: Mykola Kostenok <c_mykolak@mellanox.com>
Cc: Joel Stanley <joel@jms.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Patrick Venture <venture@google.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

drivers/hwmon/aspeed-pwm-tacho.c

@@ -830,10 +830,8 @@ static int aspeed_create_pwm_cooling(struct device *dev,
 	}
 	snprintf(cdev->name, MAX_CDEV_NAME_LEN, "%pOFn%d", child, pwm_port);
 
-	cdev->tcdev = thermal_of_cooling_device_register(child,
-							 cdev->name,
-							 cdev,
-							 &aspeed_pwm_cool_ops);
+	cdev->tcdev = devm_thermal_of_cooling_device_register(dev, child,
+					cdev->name, cdev, &aspeed_pwm_cool_ops);
 	if (IS_ERR(cdev->tcdev))
 		return PTR_ERR(cdev->tcdev);