mtd: maps: ixp4xx: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Marc Kleine-Budde <mkl@blackshift.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/maps/ixp4xx.c

@@ -155,8 +155,6 @@ static int ixp4xx_flash_remove(struct platform_device *dev)
 	struct flash_platform_data *plat = dev->dev.platform_data;
 	struct ixp4xx_flash_info *info = platform_get_drvdata(dev);
 
-	platform_set_drvdata(dev, NULL);
-
 	if(!info)
 		return 0;