[PATCH] PATCH: usb-storage: use kthread API

This patch is originally from Alan Stern (as569).  It has been rediffed
against a current tree.

This patch converts usb-storage to use the kthread API for creating its
control and scanning threads.  The new code doesn't use kthread_stop
because the threads need (or will need in the future) to exit
asynchronously.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/storage/usb.h

@@ -161,9 +161,6 @@ struct us_data {
 	struct scsi_cmnd	*srb;		 /* current srb		*/
 	unsigned int		tag;		 /* current dCBWTag	*/
 
-	/* thread information */
-	int			pid;		 /* control thread	 */
-
 	/* control and bulk communications data */
 	struct urb		*current_urb;	 /* USB requests	 */
 	struct usb_ctrlrequest	*cr;		 /* control requests	 */