block/iscsi: always fill bs->bl.opt_transfer_length

the opt_transfer_length has nothing to do with logical
block provisioning stuff so always copy it from
the block limits VPD page.
Reported-By: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

block/iscsi.c

@@ -1330,10 +1330,9 @@ static int iscsi_refresh_limits(BlockDriverState *bs)
         }
         bs->bl.write_zeroes_alignment = sector_lun2qemu(iscsilun->bl.opt_unmap_gran,
                                                         iscsilun);
-
-        bs->bl.opt_transfer_length = sector_lun2qemu(iscsilun->bl.opt_xfer_len,
-                                                     iscsilun);
     }
+    bs->bl.opt_transfer_length = sector_lun2qemu(iscsilun->bl.opt_xfer_len,
+                                                 iscsilun);
     return 0;
 }