* lib/utime.in.h: Include <time.h>.
(_gl_utimens_windows): New declaration.
* lib/utime.c (_gl_utimens_windows): New function, based on utime.
(utime): Invoke it.
* lib/utimens.c (fdutimens): On native Windows, call _gl_utimens_windows
instead of utime.
* modules/utime (Depends-on): Add 'time'.
This module, like autoconf's AC_FUNC_UTIME_NULL macro, has been
unnecessary for years, and has been marked as obsolete for 10 months.
* modules/utime: Remove file.
* lib/utime.c: Remove file.
* m4/utime.m4: Remove file.
* m4/utimes-null.m4: Remove file.
* doc/posix-functions/utime.texi (utime): Remove reference to
the module. Move the sole "fixed by gnulib" item into the
"problems not fixed by Gnulib" list.
* MODULES.html.sh (func_all_modules): Remove reference to "utime".
This provides slightly increased consistency when opening-for-write
the name of a non-directory spelled with a trailing slash.
* modules/chdir-safer: Likewise.
* modules/chown: Likewise.
* modules/clean-temp: Likewise.
* modules/copy-file: Likewise.
* modules/fchdir: Likewise.
* modules/fcntl-safer: Likewise.
* modules/pipe: Likewise.
* modules/utime: Likewise.
Prompted by Eric Blake and Bruno Haible.
