mtd: spinand: Fix OOB read

So far OOB have never been used in SPI-NAND, add the missing memcpy to
make it work properly.

Fixes: 7529df4 ("mtd: nand: Add core infrastructure to support SPI NANDs")
Cc: stable@vger.kernel.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201001102014.20100-6-miquel.raynal@bootlin.com

Author: miquelraynal

drivers/mtd/nand/spi/core.c

@@ -382,6 +382,10 @@ static int spinand_read_from_cache_op(struct spinand_device *spinand,
 		memcpy(req->databuf.in, spinand->databuf + req->dataoffs,
 		       req->datalen);
 
+	if (req->ooblen)
+		memcpy(req->oobbuf.in, spinand->oobbuf + req->ooboffs,
+		       req->ooblen);
+
 	return 0;
 }