mtd: spinand: read returns badly if the last page has bitflips

In case of the last page containing bitflips (ret > 0),
spinand_mtd_read() will return that number of bitflips for the last
page while it should instead return max_bitflips like it does when the
last page read returns with 0.
Signed-off-by: Weixiong Liao <liaoweixiong@allwinnertech.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Cc: stable@vger.kernel.org
Fixes: 7529df46 ("mtd: nand: Add core infrastructure to support SPI NANDs")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

drivers/mtd/nand/spi/core.c

@@ -511,12 +511,12 @@ static int spinand_mtd_read(struct mtd_info *mtd, loff_t from,
 		if (ret == -EBADMSG) {
 			ecc_failed = true;
 			mtd->ecc_stats.failed++;
-			ret = 0;
 		} else {
 			mtd->ecc_stats.corrected += ret;
 			max_bitflips = max_t(unsigned int, max_bitflips, ret);
 		}
 
+		ret = 0;
 		ops->retlen += iter.req.datalen;
 		ops->oobretlen += iter.req.ooblen;
 	}