x86: wmi: convert class code to use dev_groups

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

Cc: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/platform/x86/wmi.c

@@ -693,11 +693,13 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 
 	return sprintf(buf, "wmi:%s\n", guid_string);
 }
+static DEVICE_ATTR_RO(modalias);
 
-static struct device_attribute wmi_dev_attrs[] = {
-	__ATTR_RO(modalias),
-	__ATTR_NULL
+static struct attribute *wmi_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
 };
+ATTRIBUTE_GROUPS(wmi);
 
 static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
@@ -732,7 +734,7 @@ static struct class wmi_class = {
 	.name = "wmi",
 	.dev_release = wmi_dev_free,
 	.dev_uevent = wmi_dev_uevent,
-	.dev_attrs = wmi_dev_attrs,
+	.dev_groups = wmi_groups,
 };
 
 static int wmi_create_device(const struct guid_block *gblock,