hwmon: (pmbus_core) Fix pmbus_is_enabled()

Refactor pmbus_is_enabled() to return the status without any additional
processing as it is already done in _pmbus_is_enabled().

Fixes: df5f6b6a ("hwmon: (pmbus/core) Generalise pmbus get status")
Cc: stable@vger.kernel.org # v6.4
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
Link: https://lore.kernel.org/r/20230725125428.3966803-1-Naresh.Solanki@9elements.com
[groeck: Rephrased commit message]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/pmbus/pmbus_core.c

@@ -2768,7 +2768,7 @@ static int __maybe_unused pmbus_is_enabled(struct device *dev, u8 page)
 	ret = _pmbus_is_enabled(dev, page);
 	mutex_unlock(&data->update_lock);
 
-	return !!(ret & PB_OPERATION_CONTROL_ON);
+	return ret;
 }
 
 #define to_dev_attr(_dev_attr) \