scsi: introduce sdev_prefix_printk()

Like scmd_printk(), but the device name is passed in as
a string. Can be used by eg ULDs which do not have access
to the scsi_cmnd structure.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/st.c

@@ -314,8 +314,7 @@ static inline char *tape_name(struct scsi_tape *tape)
 }
 
 #define st_printk(prefix, t, fmt, a...) \
-	sdev_printk(prefix, (t)->device, "%s: " fmt, \
-		    tape_name(t), ##a)
+	sdev_prefix_printk(prefix, (t)->device, tape_name(t), fmt, ##a)
 #ifdef DEBUG
 #define DEBC_printk(t, fmt, a...) \
 	if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }