drm/nouveau: fix hwmon device binding

Bind the hwmon structs to nouveau device kobj. This makes sure
the hwmon files are created in the device subdir in line with
all other hwmon drivers.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_pm.c

@@ -422,8 +422,7 @@ nouveau_hwmon_init(struct drm_device *dev)
 		return ret;
 	}
 	dev_set_drvdata(hwmon_dev, dev);
-	ret = sysfs_create_group(&hwmon_dev->kobj,
-					&hwmon_attrgroup);
+	ret = sysfs_create_group(&dev->pdev->dev.kobj, &hwmon_attrgroup);
 	if (ret) {
 		NV_ERROR(dev,
 			"Unable to create hwmon sysfs file: %d\n", ret);