media: cobalt: remove redundant zero check on retval

The error handling paths all end up with retval being non-zero,
so the check for retval being zero is always false and hence
is redundant. Remove it.

Detected by CoverityScan CID#1309479 ("Logically dead code")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/pci/cobalt/cobalt-driver.c

@@ -767,8 +767,6 @@ err_pci:
 err_wq:
 	destroy_workqueue(cobalt->irq_work_queues);
 err:
-	if (retval == 0)
-		retval = -ENODEV;
 	cobalt_err("error %d on initialization\n", retval);
 
 	v4l2_device_unregister(&cobalt->v4l2_dev);