Bernard Xiong a5cd7e7abd Merge pull request #3944 from mysterywolf/libc		5 lat temu
..
sys	237a71de27 修复common文件夹，该文件夹为armlibc/newlib/dlib的共同文件的文件夹	5 lat temu
SConscript	b3ab8a99e1 Signed-off-by: mysterywolf	5 lat temu
readme.md	c7aa6f0619 [fix bug] #3902	5 lat temu
termios.h	237a71de27 修复common文件夹，该文件夹为armlibc/newlib/dlib的共同文件的文件夹	5 lat temu
time.c	237a71de27 修复common文件夹，该文件夹为armlibc/newlib/dlib的共同文件的文件夹	5 lat temu
unistd.c	96acad78ba 将posix_getline.h termios.h 头文件包含从<>改为""以防止路径出现分歧	5 lat temu

Attention :

This folder is "common" for armlibc newlibc and dlib. It's not "common" for minilibc.
If you want to add new .c files, please do not forget to fix SConscript file too. eg:
```
if GetDepend('RT_USING_POSIX') == False:
    SrcRemove(src, ['unistd.c'])
```