Driver Core: add ability for class_for_each_device to start in middle of list

This mirrors the functionality that driver_for_each_device has as well.

We add a start variable, and all callers of the function are fixed up at
the same time.

The block layer will be using this new functionality in a follow-on
patch.


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/i2c/i2c-core.c

@@ -722,7 +722,8 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
 
 	INIT_LIST_HEAD(&driver->clients);
 	/* Walk the adapters that are already present */
-	class_for_each_device(&i2c_adapter_class, driver, __attach_adapter);
+	class_for_each_device(&i2c_adapter_class, NULL, driver,
+			      __attach_adapter);
 
 	mutex_unlock(&core_lock);
 	return 0;
@@ -782,7 +783,8 @@ void i2c_del_driver(struct i2c_driver *driver)
 {
 	mutex_lock(&core_lock);
 
-	class_for_each_device(&i2c_adapter_class, driver, __detach_adapter);
+	class_for_each_device(&i2c_adapter_class, NULL, driver,
+			      __detach_adapter);
 
 	driver_unregister(&driver->driver);
 	pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);