Revert "driver core: check start node in klist_iter_init_node"

This reverts commit a15d49fd3094cff90e5410ca454a870e0a722fe1 as that
patch broke the build.

Cc: Hannes Reinecke <hare@suse.de>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 76aed01..2bcef65 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -296,13 +296,11 @@
 	if (!bus)
 		return -EINVAL;
 
-	error = klist_iter_init_node(&bus->p->klist_devices, &i,
-				     (start ? &start->p->knode_bus : NULL));
-	if (!error) {
-		while ((dev = next_device(&i)) && !error)
-			error = fn(dev, data);
-		klist_iter_exit(&i);
-	}
+	klist_iter_init_node(&bus->p->klist_devices, &i,
+			     (start ? &start->p->knode_bus : NULL));
+	while ((dev = next_device(&i)) && !error)
+		error = fn(dev, data);
+	klist_iter_exit(&i);
 	return error;
 }
 EXPORT_SYMBOL_GPL(bus_for_each_dev);
@@ -332,10 +330,8 @@
 	if (!bus)
 		return NULL;
 
-	if (klist_iter_init_node(&bus->p->klist_devices, &i,
-				 (start ? &start->p->knode_bus : NULL)) < 0)
-		return NULL;
-
+	klist_iter_init_node(&bus->p->klist_devices, &i,
+			     (start ? &start->p->knode_bus : NULL));
 	while ((dev = next_device(&i)))
 		if (match(dev, data) && get_device(dev))
 			break;
@@ -388,9 +384,7 @@
 		return NULL;
 
 	if (hint) {
-		if (klist_iter_init_node(&subsys->p->klist_devices, &i,
-					 &hint->p->knode_bus) < 0)
-			return NULL;
+		klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus);
 		dev = next_device(&i);
 		if (dev && dev->id == id && get_device(dev)) {
 			klist_iter_exit(&i);
@@ -452,13 +446,11 @@
 	if (!bus)
 		return -EINVAL;
 
-	error = klist_iter_init_node(&bus->p->klist_drivers, &i,
-				     start ? &start->p->knode_bus : NULL);
-	if (!error) {
-		while ((drv = next_driver(&i)) && !error)
-			error = fn(drv, data);
-		klist_iter_exit(&i);
-	}
+	klist_iter_init_node(&bus->p->klist_drivers, &i,
+			     start ? &start->p->knode_bus : NULL);
+	while ((drv = next_driver(&i)) && !error)
+		error = fn(drv, data);
+	klist_iter_exit(&i);
 	return error;
 }
 EXPORT_SYMBOL_GPL(bus_for_each_drv);
@@ -1119,19 +1111,15 @@
  * otherwise if it is NULL, the iteration starts at the beginning of
  * the list.
  */
-int subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys,
-			 struct device *start, const struct device_type *type)
+void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys,
+			  struct device *start, const struct device_type *type)
 {
 	struct klist_node *start_knode = NULL;
-	int error;
 
 	if (start)
 		start_knode = &start->p->knode_bus;
-	error = klist_iter_init_node(&subsys->p->klist_devices, &iter->ki,
-				     start_knode);
-	if (!error)
-		iter->type = type;
-	return error;
+	klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode);
+	iter->type = type;
 }
 EXPORT_SYMBOL_GPL(subsys_dev_iter_init);