[SCSI] scsi_dh_rdac : minor return fix for rdac

Signed-off-by: Babu Moger <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/device_handler/scsi_dh_rdac.c

···
 	if (!scsi_dh_data) {
 		sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
 			    RDAC_NAME);
-		return 0;
+		return -ENOMEM;
 	}
 
 	scsi_dh_data->scsi_dh = &rdac_dh;