fix bug that uffs may crash because of uninitialized device ops

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2553 bbd45198-f89e-11dd-88c7-29a3b14d5316

bsp/simulator/drivers/nanddrv_file.c

@@ -323,13 +323,20 @@ static rt_err_t nanddrv_file_erase_block(struct rt_mtd_nand_device *device, rt_u
     return RT_EOK;
 }
 
+static rt_err_t nanddrv_file_no_op(struct rt_mtd_nand_device *device, rt_uint32_t block)
+{
+    return RT_EOK;
+}
+
 const static struct rt_mtd_nand_driver_ops _ops =
 {
     nanddrv_file_read_id,
     nanddrv_file_read_page,
     nanddrv_file_write_page,
     nanddrv_file_move_page,
-    nanddrv_file_erase_block
+    nanddrv_file_erase_block,
+    nanddrv_file_no_op, /* check block */
+    nanddrv_file_no_op  /* mark bad block */
 };
 
 void nand_eraseall(void);