[m-rev.] for review: Fix unused variable warning about MERC_INT_DIR.

[Peter Wang]

Oops. The commit message should have said _undefined_ variable warnings,
not _unused_ variable warnings. (Fixed)

On Tue, 17 Oct 2023 13:59:51 +1100 "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> 
> On 2023-10-17 11:52 +11:00 AEDT, "Peter Wang" <novalazy at gmail.com> wrote:
> > scripts/Mmake.vars.in:
> >     Move the definition of MERC_INT_DIR to Mmake.vars,
> >     before its reference in MERC_INT_DIR_FOR_VPATH.
> > 
> > scripts/Mmake.rules:
> >     Delete definition of MERC_INT_DIR from Mmake.rules.
> 
> That's fine.

Thanks.

Peter