mtd: pxa3xx_nand: fix a memory leak

In pxa3xx_nand_remove, we should call nand_release instead of
mtd_device_unregister to properly free bad block table memory
and bad block descriptor memory.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Lei Wen <leiwen@marvell.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

drivers/mtd/nand/pxa3xx_nand.c

@@ -1119,7 +1119,7 @@ static int pxa3xx_nand_remove(struct platform_device *pdev)
 	clk_put(info->clk);
 
 	if (mtd) {
-		mtd_device_unregister(mtd);
+		nand_release(mtd);
 		kfree(mtd);
 	}
 	return 0;