sysfs: Add attribute array to sysdev classes

Add a attribute array that is automatically registered and unregistered
to struct sysdev_class. This is similar to what struct class has.

A lot of drivers add list of attributes, so it's better to do 
this easily in the common sysdev layer.

This adds a new field to struct sysdev_class. I audited the 
whole tree and there are no dynamically allocated sysdev classes,
so this is fully compatible. 

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>


diff --git a/include/linux/sysdev.h b/include/linux/sysdev.h
index c2458fa..b6244f9b 100644
--- a/include/linux/sysdev.h
+++ b/include/linux/sysdev.h
@@ -27,10 +27,12 @@
 
 
 struct sys_device;
+struct sysdev_class_attribute;
 
 struct sysdev_class {
 	const char *name;
 	struct list_head	drivers;
+	struct sysdev_class_attribute **attrs;
 
 	/* Default operations for these types of devices */
 	int	(*shutdown)(struct sys_device *);