mtd: atmel_nand: fix error return code in atmel_nand_probe()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Author: Wei Yongjun

drivers/mtd/nand/atmel_nand.c

@@ -2048,6 +2048,7 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
 		irq = platform_get_irq(pdev, 0);
 		if (irq < 0) {
 			dev_err(host->dev, "Cannot get HSMC irq!\n");
+			res = irq;
 			goto err_nand_ioremap;
 		}