[SCSI] hpsa: remove scan thread

The intent of the scan thread was to allow a UNIT ATTENTION/LUN
DATA CHANGED condition encountered in the interrupt handler
to trigger a rescan of devices, which can't be done in interrupt
context.  However, we weren't able to get this to work, due to
multiple such UNIT ATTENTION conditions arriving during the rescan,
during updating of the SCSI mid layer, etc.  There's no way to tell
the devices, "stand still while I scan you!"  Since it doesn't work,
there's no point in having the thread, as the rescan triggered via
ioctl or sysfs can be done without such a thread.

Signed-off-by: Mike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/hpsa.h

@@ -97,9 +97,6 @@ struct ctlr_info {
 	int			scan_finished;
 	spinlock_t		scan_lock;
 	wait_queue_head_t	scan_wait_queue;
-	struct mutex		busy_shutting_down;
-	struct list_head	scan_list;
-	struct completion	scan_wait;
 
 	struct Scsi_Host *scsi_host;
 	spinlock_t devlock; /* to protect hba[ctlr]->dev[];  */