driver core: create a private portion of struct device

This is to be used to move things out of struct device that no code
outside of the driver core should ever touch.

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

diff --git a/include/linux/device.h b/include/linux/device.h
index c56b154..4cf063f 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -28,6 +28,7 @@
 #define BUS_ID_SIZE		20
 
 struct device;
+struct device_private;
 struct device_driver;
 struct driver_private;
 struct class;
@@ -373,6 +374,8 @@
 	struct klist_node	knode_bus;
 	struct device		*parent;
 
+	struct device_private	*p;
+
 	struct kobject kobj;
 	unsigned		uevent_suppress:1;
 	const char		*init_name; /* initial name of the device */