[Toybox] [PATCH] toys.h: remove unused declaration.

[enh]

yeah, i don't have any particular use for it myself, but i accept the
"behave more like the thing you're replacing" argument and i don't see
any problem that patch would cause, so "lgtm".

-*-

mostly off topic, but personally i'd like to surface the "generally
applicable but not widely known and kind of annoying if we repeat it
everywhere it's relevant" stuff from --help:
```
The filename "-" means stdin/stdout, and "--" stops argument parsing.

Numerical arguments accept a single letter suffix for
kilo, mega, giga, tera, peta, and exabytes, plus an additional
"d" to indicate decimal 1000's instead of 1024.

Durations can be decimal fractions and accept minute ("m"), hour ("h"),
or day ("d") suffixes (so 0.1m = 6s).
```
but that shouldn't get in the way of this patch.

the args parser knows whether there are numerical arguments so it
could automatically append the bit about suffixes everywhere it's
relevant, but the durations stuff isn't known, nor is whether any
argument is a filename. and, sadly, i've been surprised by the number
of people who don't know about `--` but would feel weird adding that
everywhere. i did wonder about having "Try `toybox --help` for general
information about arguments." automatically appended everywhere but i
don't actually know whether anyone who doesn't know the stuff above
would actually look, so i haven't suggested it. (until now.)

On Wed, Oct 28, 2020 at 6:38 AM Rob Landley <rob at landley.net> wrote:
>
> On 10/27/20 6:09 PM, enh via Toybox wrote:
> > ---
> >  toys.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
>
> Sorry, a leak from an unfinished change in my tree, related to that "should
> toybox provide version info and a URL in the help" thing from endless arguing in
> the bug reports, I think the attached is the rest of it. Wasn't sure about it,
> so I hadn't checked it in.
>
> Rob