[bsp][gd32]:gd32vw553h-eval add wdt support

[ZhangYiXiSucceed]

拉取/合并请求描述：(PR description)

[

为什么提交这份PR (why to submit this PR)

add wdt support for gd32vw553h

你的解决方案是什么 (what is your solution)

请提供验证的bsp和config (provide the config and bsp)

• BSP:

• .config:

• action:

]

当前拉取/合并请求的状态 Intent for your PR

必须选择一项 Choose one (Mandatory):

• 本拉取/合并请求是一个草稿版本 This PR is for a code-review and is intended to get feedback
• 本拉取/合并请求是一个成熟版本 This PR is mature, and ready to be integrated into the repo

代码质量 Code Quality：

我在这个拉取/合并请求中已经考虑了 As part of this pull request, I've considered the following:

• 已经仔细查看过代码改动的对比 Already check the difference between PR and old code
• 代码风格正确，包括缩进空格，命名及其他风格 Style guide is adhered to, including spacing, naming and other styles
• 没有垃圾代码，代码尽量精简，不包含#if 0代码，不包含已经被注释了的代码 All redundant code is removed and cleaned up
• 所有变更均有原因及合理的，并且不会影响到其他软件组件代码或BSP All modifications are justified and not affect other components or BSP
• 对难懂代码均提供对应的注释 I've commented appropriately where code is tricky
• 代码是高质量的 Code in this PR is of high quality
• 已经使用formatting 等源码格式化工具确保格式符合RT-Thread代码规范 This PR complies with RT-Thread code specification
• 如果是新增bsp, 已经添加ci检查到.github/ALL_BSP_COMPILE.json 详细请参考链接BSP自查

[github-actions]

👋 感谢您对 RT-Thread 的贡献！Thank you for your contribution to RT-Thread!

为确保代码符合 RT-Thread 的编码规范，请在你的仓库中执行以下步骤运行代码格式化工作流（如果格式化CI运行失败）。
To ensure your code complies with RT-Thread's coding style, please run the code formatting workflow by following the steps below (If the formatting of CI fails to run).

---

🛠 操作步骤 | Steps

1. 前往 Actions 页面 | Go to the Actions page
   点击进入工作流 → | Click to open workflow →

2. 点击 Run workflow | Click Run workflow

• 设置需排除的文件/目录（目录请以"/"结尾）
  Set files/directories to exclude (directories should end with "/")
• 将目标分支设置为 \ Set the target branch to：feature/gd32vw553h-eval-add-wdt-support
• 设置PR number为 \ Set the PR number to：11181

3. 等待工作流完成 | Wait for the workflow to complete
   格式化后的代码将自动推送至你的分支。
   The formatted code will be automatically pushed to your branch.

完成后，提交将自动更新至 feature/gd32vw553h-eval-add-wdt-support 分支，关联的 Pull Request 也会同步更新。
Once completed, commits will be pushed to the feature/gd32vw553h-eval-add-wdt-support branch automatically, and the related Pull Request will be updated.

如有问题欢迎联系我们，再次感谢您的贡献！💐
If you have any questions, feel free to reach out. Thanks again for your contribution!

[Rbb666]

请为wdt驱动添加ci-attach

参考：https://club.rt-thread.org/ask/article/5edd0f0940a57129.html

[Copilot]

Pull request overview

This PR aims to add Watchdog Timer (WDT) support for the GD32VW553H-EVAL BSP by introducing a new WDT driver, wiring it into the GD32 RISC-V driver build, and exposing WDT-related Kconfig options for the board.

Changes:

• Add a new GD32 RISC-V watchdog driver (drv_wdt.c) implementing RT-Thread watchdog device ops.
• Update SConscript to compile the WDT driver when RT_USING_WDT + SOC_GD32VW553H are enabled.
• Extend board Kconfig to expose WDT options (and also UART3/UART4 options).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 11 comments.

File	Description
bsp/gd32/risc-v/libraries/gd32_drivers/drv_wdt.c	New watchdog driver implementation plus shell test commands
bsp/gd32/risc-v/libraries/gd32_drivers/SConscript	Adds conditional compilation of drv_wdt.c for GD32VW553H
bsp/gd32/risc-v/gd32vw553h-eval/board/Kconfig	Adds board-level WDT configs (and UART3/4 related configs)

[Rbb666]

@ZhangYiXiSucceed 还请根据 ai 的一些建议修正下 pr 存在的问题，谢谢