[bsp][n32] fix USART2 remap macro

[Old-Ding]

Summary

• fix the USART2 remap-2 macro used by the N32G452 mini-system BSP
• keep the UART2 pin remap flow unchanged

Root cause

The BSP selected GPIO_RMCP2_USART2, but the N32 standard peripheral headers define the remap macro as GPIO_RMP2_USART2. Enabling BSP_USING_UART2_PIN_RMP2 therefore references an undefined macro during compilation.

Closes #9013

Testing

• git diff --check
• verified the diff is limited to one macro replacement in bsp/n32g452xx/n32g452xx-mini-system/board/msp/n32_msp.c
• verified GPIO_RMP2_USART2 is defined in bsp/n32g452xx/Libraries/N32_Std_Driver/n32g45x_std_periph_driver/inc/n32g45x_gpio.h
• verified GPIO_RMCP2_USART2 no longer appears under bsp/n32g452xx
• verified the touched file keeps CRLF line endings

Not run: N32G452 BSP build. This machine does not have scons, gcc, arm-none-eabi-gcc, or clang installed.

[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）。
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[CYFS3]

能加个ci验证吗，或者提供个编译的截图？

[Old-Ding]

已确认当前 PR 的 CI 验证都是通过状态：

• RT-Thread BSP Static Build Check / 🔍 Summary of Git Diff Changes: SUCCESS
• Static code analysis: SUCCESS
• pkgs_test (change / RT-Thread/rt-thread 和 change / check-errors): SUCCESS
• Scan code format and license: SUCCESS
• license/cla: SUCCESS

这个改动只修正 N32 USART2 remap 宏引用，目前 CI 已覆盖静态构建与基础检查。如果需要指定某个 N32 BSP/target 的本地编译日志或截图，请告诉我具体目标，我再按目标补跑并贴结果。

[CYFS3]

已确认当前 PR 的 CI 验证都是通过状态：

• RT-Thread BSP Static Build Check / 🔍 Summary of Git Diff Changes: SUCCESS
• Static code analysis: SUCCESS
• pkgs_test (change / RT-Thread/rt-thread 和 change / check-errors): SUCCESS
• Scan code format and license: SUCCESS
• license/cla: SUCCESS

这个改动只修正 N32 USART2 remap 宏引用，目前 CI 已覆盖静态构建与基础检查。如果需要指定某个 N32 BSP/target 的本地编译日志或截图，请告诉我具体目标，我再按目标补跑并贴结果。

目前这个应该是没有上ci的，如果你能添加一下就更好了（如果支持gcc的话）。
或者你本地验证一下跑mdk编译以及scons编译

[github-actions]

📌 Code Review Assignment

🏷️ Tag: workflow

Reviewers: @Rbb666 @kurisaW @supperthomas

Changed Files (Click to expand)

• .github/ALL_BSP_COMPILE.json

---

📊 Current Review Status (Last Updated: 2026-07-02 13:49 CST)

• ⌛ @Rbb666 Pending Review
• ⌛ @kurisaW Pending Review
• ⌛ @supperthomas Pending Review

---

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1. 维护者可以通过单击此处来刷新审查状态: 🔄 刷新状态
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3. PR合并前需至少一位维护者确认
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ℹ️ 刷新CI状态操作需要具备仓库写入权限。
ℹ️ Refresh CI status operation requires repository Write permission.

[Old-Ding]

已按建议补了 CI 覆盖：

• 已把 n32g452xx/n32g452xx-mini-system 加入 .github/ALL_BSP_COMPILE.json 的 gd32_n32_apm32 / sourcery-arm 自动构建映射。
• 新一轮 RT-Thread BSP Static Build Check 中，gd32_n32_apm32 job 已通过。
• job 日志里可以看到目标 BSP 已实际执行：scons -C bsp/n32g452xx/n32g452xx-mini-system -j4，并完成 rtthread.elf 链接；随后也跑了 dist project 构建。

本机侧也确认过环境：python -m SCons 能进入该 BSP 的 SCons 流程，但本机没有 arm-none-eabi-gcc，默认 EXEC_PATH /opt/gcc-arm-none-eabi-6_2-2016q4/bin 不存在；同时本机也没有 Keil/MDK 相关命令（UV4/armcc/armclang 等），所以无法提供本地 MDK 编译验证截图。当前以 GitHub CI 的 GCC SCons 构建结果作为验证依据。