GenWQE: use kobj_to_dev()

Use kobj_to_dev() instead of open-coding it.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/genwqe/card_sysfs.c

@@ -278,7 +278,7 @@ static umode_t genwqe_is_visible(struct kobject *kobj,
 				 struct attribute *attr, int n)
 {
 	unsigned int j;
-	struct device *dev = container_of(kobj, struct device, kobj);
+	struct device *dev = kobj_to_dev(kobj);
 	struct genwqe_dev *cd = dev_get_drvdata(dev);
 	umode_t mode = attr->mode;