mtd: nand: plat_nand: return error code of nand_scan() on error

The nand_scan() returns an appropriate error value when it fails.
Use it instead of the fixed error code -ENXIO.

Signed-off-by: Masahiro Yamada <[e-mail]>
Reviewed-by: Marek Vasut <[e-mail]>
Signed-off-by: Boris Brezillon <[e-mail]>

drivers/mtd/nand/plat_nand.c

···
 	}
 
 	/* Scan to find existence of the device */
-	if (nand_scan(mtd, pdata->chip.nr_chips)) {
-		err = -ENXIO;
+	err = nand_scan(mtd, pdata->chip.nr_chips);
+	if (err)
 		goto out;
-	}
 
 	part_types = pdata->chip.part_probe_types;