UBI: account for bitflips in both the VID header and data

commit 8eef7d70 upstream.

We are completely discarding the earlier value of 'bitflips', which
could reflect a bitflip found in ubi_io_read_vid_hdr(). Let's use the
bitwise OR of header and data 'bitflip' statuses instead.

Coverity CID #1226856
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/mtd/ubi/scan.c

@@ -408,7 +408,7 @@ static int compare_lebs(struct ubi_device *ubi, const struct ubi_scan_leb *seb,
 		second_is_newer = !second_is_newer;
 	} else {
 		dbg_bld("PEB %d CRC is OK", pnum);
-		bitflips = !!err;
+		bitflips |= !!err;
 	}
 
 	vfree(buf);