legacy stdc++: Drop <iostdio.h>.

It couldn't have been used anywhere, because "iolibio.h" is
available only in glibc includes in libroot, not in the
"headers" directories.

headers/cpp/iostdio.h

@@ -1,114 +0,0 @@
-/*
-Copyright (C) 1993 Free Software Foundation
-
-This file is part of the GNU IO Library.  This library is free
-software; you can redistribute it and/or modify it under the
-terms of the GNU General Public License as published by the
-Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this library; see the file COPYING.  If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
-
-As a special exception, if you link this library with files
-compiled with a GNU compiler to produce an executable, this does not cause
-the resulting executable to be covered by the GNU General Public License.
-This exception does not however invalidate any other reasons why
-the executable file might be covered by the GNU General Public License. */
-
-/* This file defines a stdio-like environment, except that it avoid
-   link-time name clashes with an existing stdio.
-   It allows for testing the libio using stdio-using programs
-   with an incompatible libc.a.
-   It is not predantically correct - e.g. some macros are used
-   that may evaluate a stream argument more than once.  */
-
-#ifndef _IOSTDIO_H
-#define _IOSTDIO_H
-
-#include "iolibio.h"
-
-typedef _IO_FILE FILE;
-#ifndef EOF
-#define EOF (-1)
-#endif
-#ifndef BUFSIZ
-#define BUFSIZ 8192
-#endif
-
-/* #define size_t, fpos_t L_tmpname TMP_MAX */
-
-#define _IOFBF 0 /* Fully buffered. */
-#define _IOLBF 1 /* Line buffered. */
-#define _IONBF 2 /* No buffering. */
-
-#define SEEK_SET 0
-#define SEEK_CUR 1
-#define SEEK_END 2
-
-#define stdin _IO_stdin
-#define stdout _IO_stdout
-#define stderr _IO_stderr
-
-#define getc(_fp) _IO_getc(_fp)
-#define putc(_ch, _fp) _IO_putc(_ch, _fp)
-
-#define clearerr _IO_clearerr
-#define fclose _IO_fclose
-#define feof _IO_feof
-#define ferror _IO_ferror
-#define fflush _IO_fflush
-#define fgetc(__fp) _IO_getc(_fp)
-#define fgetpos _IO_fgetpos
-#define fgets _IO_fgets
-#define fopen _IO_fopen
-#define fprintf _IO_fprintf
-#define fputc(_ch, _fp) _IO_putc(_ch, _fp)
-#define fputs _IO_fputs
-#define fread _IO_fread
-#define freopen _IO_freopen
-#define fscanf _IO_fscanf
-#define fseek _IO_fseek
-#define fsetpos _IO_fsetpos
-#define ftell _IO_ftell
-#define fwrite _IO_fwrite
-#define gets _IO_gets
-#define perror _IO_perror
-#define printf _IO_printf
-#define puts _IO_puts
-#define rewind _IO_rewind
-#define scanf _IO_scanf
-#define setbuf _IO_setbuf
-#define setbuffer _IO_setbuffer
-#define setvbuf _IO_setvbuf
-#define sprintf _IO_sprintf
-#define sscanf _IO_sscanf
-#define ungetc _IO_ungetc
-#define vfprintf _IO_vfprintf
-#define vprintf(__fmt, __args) vfprintf(stdout, __fmt, __args)
-#define vsprintf _IO_vsprintf
-
-#if 0
-/* We can use the libc versions of these, since they don't pass FILE*s. */
-#define remove ??? __P((const char*))
-#define rename ??? __P((const char* _old, const char* _new))
-#define tmpfile ??? __P((void))
-#define tmpnam ??? __P((char*))
-#endif
-
-#if !defined(__STRICT_ANSI__) || defined(_POSIX_SOURCE)
-#define fdopen _IO_fdopen
-#define fileno _IO_fileno
-#define popen _IO_popen
-#define pclose _IO_pclose
-#define setbuf _IO_setbuf
-#define setlinebuf _IO_setlinebuf
-#endif
-
-#endif /* _IOSTDIO_H */