[Bug] examples/utest/testcases/posix 下部分代码是 GPL 的，和 RT-Thread 的 Apache 授权冲突

[unicornx]

RT-Thread Version

master

Hardware Type/Architectures

N/A

Develop Toolchain

GCC

Describe the bug

examples/utest/testcases/posix/ 下有不少文件的代码标识了采用 GPL 授权。
主要包括：

• examples/utest/testcases/posix/ctype_h/definitions/ctype_h.c
• examples/utest/testcases/posix/pthread_h/ 下的部分代码
• examples/utest/testcases/posix/stdio_h/definitions/stdio_h.c
• examples/utest/testcases/posix/stdlib_h/definitions/stdlib_h.c

特别地，pthread 部分的代码看上去是直接从 LTP 拿来的，而 LTP 遵循的是 GPLv2/GPL，see https://github.com/linux-test-project/ltp/blob/master/COPYING。

参考：https://www.apache.org/licenses/GPL-compatibility.html

Apache 2 software can therefore be included in GPLv3 projects, because the GPLv3 license accepts our software into GPLv3 works. However, GPLv3 software cannot be included in Apache projects. The licenses are incompatible in one direction only, and it is a result of ASF's licensing philosophy and the GPLv3 authors' interpretation of copyright law.

所以我认为 Apache license 的 RT-Thread 包含了 GPL 的代码也是不恰当的，会有潜在的法律问题。

Other additional context

No response