tweak wcwidth.m4

[Bruno Haible]

wcwidth.m4 was using HAVE_STRING_H without testing whether <string.h>
exists. Of course, we nowadays assume it exists.


2006-07-30  Bruno Haible  <address@hidden>

        * wcwidth.m4 (gl_FUNC_WCWIDTH): Assume <string.h> exists.

*** m4/wcwidth.m4.bak   2006-07-03 13:53:03.000000000 +0200
--- m4/wcwidth.m4       2006-07-30 22:45:40.000000000 +0200
***************
*** 1,4 ****
! # wcwidth.m4 serial 3
  dnl Copyright (C) 2006 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
--- 1,4 ----
! # wcwidth.m4 serial 4
  dnl Copyright (C) 2006 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
***************
*** 17,25 ****
  
    AC_CHECK_DECLS([wcwidth], [], [], [
  /* AIX 3.2.5 declares wcwidth in <string.h>. */
! #if HAVE_STRING_H
! # include <string.h>
! #endif
  #if HAVE_WCHAR_H
  # include <wchar.h>
  #endif
--- 17,23 ----
  
    AC_CHECK_DECLS([wcwidth], [], [], [
  /* AIX 3.2.5 declares wcwidth in <string.h>. */
! #include <string.h>
  #if HAVE_WCHAR_H
  # include <wchar.h>
  #endif