【CMAKE】自动识别子目录，并添加add_subdirectory调用

# 获取目录下的子目录名
# subdirnamelist 子目录名称列表，输出变量，调用处定义，填充时不能加${}
# targetdir      目标路径，为全路径
macro(SUBDIRNAMELIST_MACRO subdirnamelist targetdir)
    # message(STATUS "macro subdirnamelist = ${subdirnamelist}")
    # message(STATUS "macro targetdir = ${targetdir}")
    file(GLOB children ${targetdir}/*) # 获取目标路径下的内容，深度为1
    # message(STATUS "macro children = ${children}")
    set(dirlist "")
    foreach(child ${children})
        file(RELATIVE_PATH child_name ${targetdir} ${child}) # 通过相对路径计算获取名称
        # message(STATUS "macro child = ${child_name}")
        # message(STATUS "targetdir/child = ${targetdir}/${child_name}")
        if(IS_DIRECTORY ${targetdir}/${child_name})
            # message(STATUS "yes dir : targetdir/child = ${targetdir}/${child_name}")
            list(APPEND dirlist ${child_name})
        endif()
    endforeach()
    list(APPEND ${subdirnameli