nand_util.c: Use '%zd' for length in nand_unlock debug print

length is size_t so needs to be '%zd' not '%d' to avoid warnings.

Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Tom Rini <trini@ti.com>

drivers/mtd/nand/nand_util.c

@@ -315,7 +315,7 @@ int nand_unlock(struct mtd_info *mtd, loff_t start, size_t length,
 	int page;
 	struct nand_chip *chip = mtd->priv;
 
-	debug("nand_unlock%s: start: %08llx, length: %d!\n",
+	debug("nand_unlock%s: start: %08llx, length: %zd!\n",
 		allexcept ? " (allexcept)" : "", start, length);
 
 	/* select the NAND device */