mtd: maps: rbtx4939-flash: show parent device in sysfs

Fix a bug where mtd parent device symlinks aren't shown in sysfs.

While at it, make use of the default owner value set by mtdcore.
Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/maps/rbtx4939-flash.c

@@ -96,7 +96,7 @@ static int rbtx4939_flash_probe(struct platform_device *dev)
 		err = -ENXIO;
 		goto err_out;
 	}
-	info->mtd->owner = THIS_MODULE;
+	info->mtd.dev.parent = &dev->dev;
 	err = mtd_device_parse_register(info->mtd, NULL, NULL, pdata->parts,
 					pdata->nr_parts);