driver core: devcoredump: convert to use class_groups

Convert devcoredump to use class_groups instead of class_attrs as that's
the correct way to handle lists of class attribute files.
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/devcoredump.c

@@ -160,18 +160,20 @@ static ssize_t disabled_store(struct class *class, struct class_attribute *attr,
 
 	return count;
 }
+static CLASS_ATTR_RW(disabled);
 
-static struct class_attribute devcd_class_attrs[] = {
-	__ATTR_RW(disabled),
-	__ATTR_NULL
+static struct attribute *devcd_class_attrs[] = {
+	&class_attr_disabled.attr,
+	NULL,
 };
+ATTRIBUTE_GROUPS(devcd_class);
 
 static struct class devcd_class = {
 	.name		= "devcoredump",
 	.owner		= THIS_MODULE,
 	.dev_release	= devcd_dev_release,
 	.dev_groups	= devcd_dev_groups,
-	.class_attrs	= devcd_class_attrs,
+	.class_groups	= devcd_class_groups,
 };
 
 static ssize_t devcd_readv(char *buffer, loff_t offset, size_t count,