[Toybox] this week in weird coreutils stuff: chmod

[enh]

seems to have broken the macOS build?
```
lib/lib.c:953:10: error: conflicting types for 'string_to_mode'
unsigned string_to_mode(char *modestr, unsigned mode)
         ^
./lib/lib.h:413:10: note: previous declaration is here
unsigned string_to_mode(char *mode_str, mode_t base);
         ^
```

On Wed, May 29, 2024 at 12:29 PM Rob Landley <rob at landley.net> wrote:
>
> On 5/28/24 08:00, enh via Toybox wrote:
> > apparently chmod allows something like
> >
> >   chmod u+rwX-s,g+rX-ws,o+rX-wt
> >
> > as a (far less readable!) synonym for
> >
> >   chmod u+rwX,u-s,g+rX,g-ws,o+rX,o-wt
> >
> > i'm told that toybox silently accepts the former too, but does not
> > interpret it as if it means the latter?
>
> Try commit a2c4a53e155c.
>
> (Needed to zero a variable inside the loop rather than just once at the
> beginning. Random cleanups while I was there, plus tests.)
>
> Rob