powerpc: vio: use dev_groups and not dev_attrs for bus_type

The dev_attrs field has long been "depreciated" and is finally being
removed, so move the driver to use the "correct" dev_groups field
instead for struct bus_type.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: <linuxppc-dev@lists.ozlabs.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/powerpc/platforms/pseries/vio.c

@@ -1537,6 +1537,7 @@ static ssize_t name_show(struct device *dev,
 {
 	return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 }
+static DEVICE_ATTR_RO(name);
 
 static ssize_t devspec_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
@@ -1545,6 +1546,7 @@ static ssize_t devspec_show(struct device *dev,
 
 	return sprintf(buf, "%s\n", of_node_full_name(of_node));
 }
+static DEVICE_ATTR_RO(devspec);
 
 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
@@ -1566,13 +1568,15 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 
 	return sprintf(buf, "vio:T%sS%s\n", vio_dev->type, cp);
 }
+static DEVICE_ATTR_RO(modalias);
 
-static struct device_attribute vio_dev_attrs[] = {
-	__ATTR_RO(name),
-	__ATTR_RO(devspec),
-	__ATTR_RO(modalias),
-	__ATTR_NULL
+static struct attribute *vio_dev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_devspec.attr,
+	&dev_attr_modalias.attr,
+	NULL,
 };
+ATTRIBUTE_GROUPS(vio_dev);
 
 void vio_unregister_device(struct vio_dev *viodev)
 {
@@ -1608,7 +1612,7 @@ static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
 
 struct bus_type vio_bus_type = {
 	.name = "vio",
-	.dev_attrs = vio_dev_attrs,
+	.dev_groups = vio_dev_groups,
 	.uevent = vio_hotplug,
 	.match = vio_bus_match,
 	.probe = vio_bus_probe,