[SCSI] fix uninitialized variable error

in __scsi_add_device, sdev may be uninitialised if
scsi_host_scan_allowed() returns false.  Fix by initialising at the
top of the routine.  Also rely on the fact that
scsi_probe_and_add_lun() only actually fills in the sdev pointer if
the SCSI_SCAN_LUN_PRESENT case (so no need to check the return value).
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/scsi_scan.c

@@ -1243,9 +1243,8 @@ static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
 				      uint id, uint lun, void *hostdata)
 {
-	struct scsi_device *sdev;
+	struct scsi_device *sdev = ERR_PTR(-ENODEV);
 	struct device *parent = &shost->shost_gendev;
-	int res;
 	struct scsi_target *starget;
 
 	starget = scsi_alloc_target(parent, channel, id);
@@ -1254,12 +1253,8 @@ struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
 
 	get_device(&starget->dev);
 	mutex_lock(&shost->scan_mutex);
-	if (scsi_host_scan_allowed(shost)) {
-		res = scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1,
-					     hostdata);
-		if (res != SCSI_SCAN_LUN_PRESENT)
-			sdev = ERR_PTR(-ENODEV);
-	}
+	if (scsi_host_scan_allowed(shost))
+		scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
 	mutex_unlock(&shost->scan_mutex);
 	scsi_target_reap(starget);
 	put_device(&starget->dev);