* libc/stdio/vprintf.c (vprintf): fix signature to use _DEFUN
* libc/stdio/vprintf.c (_vprintf_r): new function
* libc/stdio/vsnprintf.c (vsnprintf): fix signature to use _DEFUN
* libc/stdio/vsnprintf.c (_vsnprintf_r): fix signature to use
_DEFUN, and call _vfprintf_r, not vfprintf.
* libc/stdio/vsprintf.c (vsprintf.c): fix signature to use _DEFUN
* libc/stdio/vsprintf.c (_vsprintf_r): fix signature to use
_DEFUN, and call _vfprintf_r, not vfprintf.