[m-rev.] for review: Fix --track-flags.

[Julien Fischer]

On Thu, 3 Jun 2021, Peter Wang wrote:

> Commit 181ada0dbf2899b388ae9155083a3050dd027cc1 changed many options
> from normal options to special options. This revealed a bug in the
> implementation of --track-flags. We previously computed the hash of a
> list of (option, option_data) pairs to detect if options differ from a
> previous run. However, for special options, the option_data is always
> bool_special, int_special, etc. so whatever value those options
> were set to had no effect on the hash value.
>
> compiler/make.m:
>    Include the opt_tuple table when computing the hash for
>    `.track_flags' files.

That's fine.

Julien.