fix(risc-v, mmu): fix type mismatch of return type of _query

[Tang-Haojin]

拉取/合并请求描述：(PR description)

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为什么提交这份PR (why to submit this PR)

在 rt_hw_mmu_control 中，_query 函数的返回值类型为 rt_ubase_t *，这与后续的 control_handler() 的输入参数类型 rt_base_t * 不符。

libcpu/risc-v/common64/mmu.c:575:24: warning: initializing 'rt_base_t *' (aka 'long *') with an expression of type 'rt_ubase_t *' (aka 'unsigned long *') converts between pointers to integer types with different sign [-Wpointer-sign]
  575 |             rt_base_t *pte = _query(aspace, vaddr, &level);
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你的解决方案是什么 (what is your solution)

将后续的 control_handler() 的输入参数类型修改为 rt_ubase_t *。这是自然的，因为 _query 返回的是 pte，一般来讲被认为是一个无符号的量。

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

• BSP: bsp/qemu-virt64-riscv

• .config: 默认配置，无需额外修改

• action:

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当前拉取/合并请求的状态 Intent for your PR

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• 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]

📌 Code Review Assignment

🏷️ Tag: libcpu_riscv

Reviewers: @Yaochenger

Changed Files (Click to expand)

• libcpu/risc-v/common64/mmu.c

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📊 Current Review Status (Last Updated: 2025-09-01 15:39 CST)

• ⌛ @Yaochenger Pending Review

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