wchar.h: supply WEOF on Irix 5.3 * lib/wchar.in.h (wint_t): Also supply WEOF. * lib/wctype.in.h (wint_t): Likewise. * doc/posix-headers/wchar.texi (wchar.h): Document the bug. * doc/posix-headers/wctype.texi (wctype.h): Likewise. Reported by Tom G. Christensen. Signed-off-by: Eric Blake <ebb9@byu.net>