UBI: fix forward compatibility

Commit 0798cea "UBI: improve corrupted flash handling"
broke delet-compatible volumes handling - it introduced a limit of 8 eraseblocks which
may be corrupted. And delete-compatible eraseblocks are added to the "corrupted" list,
so if we'd have a large delete-compatible volume, UBI would refuse it.

The fix is to add delete-compatible volumes to the erase list instead. Indeed, they are
corrupted, we just have to erase them.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

drivers/mtd/ubi/scan.c

@@ -843,7 +843,7 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si,
 		case UBI_COMPAT_DELETE:
 			ubi_msg("\"delete\" compatible internal volume %d:%d"
 				" found, will remove it", vol_id, lnum);
-			err = add_to_list(si, pnum, ec, &si->corr);
+			err = add_to_list(si, pnum, ec, &si->erase);
 			if (err)
 				return err;
 			return 0;