ncr5380: Use work_struct instead of delayed_work

Each host instance now has it's own work queue so the main() work item can
sleep when necessary. That means we can use a simple work item rather than
a delayed work item. This brings NCR5380.c closer to atari_NCR5380.c.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/NCR5380.h

@@ -256,7 +256,6 @@ struct NCR5380_hostdata {
 	volatile struct scsi_cmnd *issue_queue;	/* waiting to be issued */
 	volatile struct scsi_cmnd *disconnected_queue;	/* waiting for reconnect */
 	int flags;
-	struct delayed_work coroutine;		/* our co-routine */
 	struct scsi_eh_save ses;
 	char info[256];
 	int read_overruns;                /* number of bytes to cut from a