fix:内源代码检视修改（安全函数）

【背景】3.1代码review问题修改

【修改方案】
 根据检视意见对安全函数使用不当进行修改

Signed-off-by: x_xiny <1301913191@qq.com>
Change-Id: I970bb6c188a153fdb2d8e8d3cf11a90930478c3d

drivers/usbdev/gadget/fconfig/src/usbd_generic_ep0.c

@@ -1183,7 +1183,7 @@ int generic_create_ep0(struct generic_dev_s *dev)
       goto err;
     }
   ret = strncat_s(dev_name, GENERIC_PATH_LEN, "/ep0", strlen("/ep0"));
-  if (ret < 0)
+  if (ret != EOK)
     {
       usb_err("usb make ep0 file path error! ret = %d, errono = %d\n",
               ret, get_errno());