fix struct user_info export's sysfs interaction

Clean up the use of ksets and kobjects. Kobjects are instances of
objects (like struct user_info), ksets are collections of objects of a
similar type (like the uids directory containing the user_info directories).
So, use kobjects for the user_info directories, and a kset for the "uids"
directory.

On object cleanup, the final kobject_put() was missing.

Cc: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/ksysfs.c

@@ -141,11 +141,8 @@ static int __init ksysfs_init(void)
 			goto group_exit;
 	}
 
-	/*
-	 * Create "/sys/kernel/uids" directory and corresponding root user's
-	 * directory under it.
-	 */
-	error = uids_kobject_init();
+	/* create the /sys/kernel/uids/ directory */
+	error = uids_sysfs_init();
 	if (error)
 		goto notes_exit;