scsi: core: scsi_get_device_flags_keyed(): Always return device flags

Since scsi_get_device_flags_keyed() callers do not check whether or not
the returned value is an error code, change that function such that it
returns a flags value even if the 'key' argument is invalid.  Note:
since commit 28a0bc41 ("scsi: sd: Implement blacklist option for
WRITE SAME w/ UNMAP") bit 31 is a valid device information flag so
checking whether bit 31 is set in the return value is not sufficient to
tell the difference between an error code and a flags value.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/scsi_devinfo.c

@@ -599,17 +599,12 @@ blist_flags_t scsi_get_device_flags_keyed(struct scsi_device *sdev,
 				int key)
 {
 	struct scsi_dev_info_list *devinfo;
-	int err;
 
 	devinfo = scsi_dev_info_list_find(vendor, model, key);
 	if (!IS_ERR(devinfo))
 		return devinfo->flags;
 
-	err = PTR_ERR(devinfo);
-	if (err != -ENOENT)
-		return err;
-
-	/* nothing found, return nothing */
+	/* key or device not found: return nothing */
 	if (key != SCSI_DEVINFO_GLOBAL)
 		return 0;