staging: fieldbus: use kobj_to_dev() to get device

Use kobj_to_dev() instead of container_of()

Signed-off-by: Ding Xiang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/fieldbus/dev_core.c

···
 static umode_t fieldbus_is_visible(struct kobject *kobj, struct attribute *attr,
 				   int n)
 {
-	struct device *dev = container_of(kobj, struct device, kobj);
+	struct device *dev = kobj_to_dev(kobj);
 	struct fieldbus_dev *fb = dev_get_drvdata(dev);
 	umode_t mode = attr->mode;