extcon: convert extcon_class to use dev_groups

The dev_attrs field of struct class is going away soon, dev_groups
should be used instead. This converts the extcon_class code to use the
correct field.

Cc: MyungJoo Ham <[e-mail]>
Acked-by: Chanwoo Choi<[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/extcon/extcon-class.c

···
 
 	return count;
 }
+static DEVICE_ATTR_RW(state);
 
 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 		char *buf)
···
 
 	return sprintf(buf, "%s\n", dev_name(edev->dev));
 }
+static DEVICE_ATTR_RO(name);
 
 static ssize_t cable_name_show(struct device *dev,
 			       struct device_attribute *attr, char *buf)
···
 }
 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
 
-static struct device_attribute extcon_attrs[] = {
-	__ATTR(state, S_IRUGO | S_IWUSR, state_show, state_store),
-	__ATTR_RO(name),
-	__ATTR_NULL,
+static struct attribute *extcon_attrs[] = {
+	&dev_attr_state.attr,
+	&dev_attr_name.attr,
+	NULL,
 };
+ATTRIBUTE_GROUPS(extcon);
 
 static int create_extcon_class(void)
 {
···
 		extcon_class = class_create(THIS_MODULE, "extcon");
 		if (IS_ERR(extcon_class))
 			return PTR_ERR(extcon_class);
-		extcon_class->dev_attrs = extcon_attrs;
+		extcon_class->dev_groups = extcon_groups;
 
 #if defined(CONFIG_ANDROID)
 		switch_class = class_compat_register("switch");