scsi_dh_hp_sw: fix return value on failed allocation

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
diff --git a/drivers/scsi/device_handler/scsi_dh_hp_sw.c b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
index 4ee2759..4824bfb 100644
--- a/drivers/scsi/device_handler/scsi_dh_hp_sw.c
+++ b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
@@ -364,7 +364,7 @@
 	if (!scsi_dh_data) {
 		sdev_printk(KERN_ERR, sdev, "%s: Attach Failed\n",
 			    HP_SW_NAME);
-		return 0;
+		return -ENOMEM;
 	}
 
 	scsi_dh_data->scsi_dh = &hp_sw_dh;