doc: update Upload API description

components/upload/index.en-US.md

@@ -29,7 +29,7 @@ Uploading is the process of publishing information (web pages, text, pictures, v
 | showUploadList | Whether to show default upload list, could be an object to specify `showPreviewIcon` and `showRemoveIcon` individually | Boolean or { showPreviewIcon?: boolean, showRemoveIcon?: boolean } | true |
 | multiple   | Whether to support selected multiple file. `IE10+` supported. You can select multiple files with CTRL holding down while multiple is set to be true  | boolean     | false |
 | accept     | File types that can be accepted. See [input accept Attribute](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attr-accept)    | string      | -   |
-| beforeUpload | Hook function which will be executed before uploading. Uploading will be stopped with `false` or a rejected Promise returned. **Warning：this function is not supported by old IE**。 | (file, fileList) => `boolean | Promise`    | -    |
+| beforeUpload | Hook function which will be executed before uploading. Uploading will be stopped with `false` or a rejected Promise returned. **Warning：this function is not supported in IE9**。 | (file, fileList) => `boolean | Promise`    | -    |
 | customRequest | override for the default xhr behavior allowing for additional customization and ability to implement your own XMLHttpRequest | Function | - |
 | onChange   | A callback function, can be executed when uploading state is changing. See [onChange](#onChange)                | Function    | -   |
 | listType   | Built-in stylesheets, support for three types: `text`, `picture` or `picture-card`     | string      | 'text'|

components/upload/index.zh-CN.md

@@ -30,7 +30,7 @@ title: Upload
 | showUploadList | 是否展示 uploadList, 可设为一个对象，用于单独设定 showPreviewIcon 和 showRemoveIcon | Boolean or { showPreviewIcon?: boolean, showRemoveIcon?: boolean } | true |
 | multiple   | 是否支持多选文件，`ie10+` 支持。开启后按住 ctrl 可选择多个文件。  | boolean     | false |
 | accept     | 接受上传的文件类型, 详见 [input accept Attribute](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attr-accept)    | string      | 无    |
-| beforeUpload | 上传文件之前的钩子，参数为上传的文件，若返回 `false` 则停止上传。支持返回一个 Promise 对象，Promise 对象 reject 时则停止上传，resolve 时开始上传。**注意：该方法不支持老 IE**。 | (file, fileList) => `boolean | Promise`    | 无    |
+| beforeUpload | 上传文件之前的钩子，参数为上传的文件，若返回 `false` 则停止上传。支持返回一个 Promise 对象，Promise 对象 reject 时则停止上传，resolve 时开始上传。**注意：IE9 不支持该方法**。 | (file, fileList) => `boolean | Promise`    | 无    |
 | customRequest | 通过覆盖默认的上传行为，可以自定义自己的上传实现 | Function | 无 |
 | onChange   | 上传文件改变时的状态，详见 [onChange](#onChange)                | Function    | 无    |
 | listType   | 上传列表的内建样式，支持三种基本样式 `text`, `picture` 和 `picture-card`     | string      | 'text'|