Updating menhir

[julien.puydt@gmail.com]

Hi,

I updated menhir on salsa to the last upstream -- and in the process,
it got a +ds suffix because I kicked the prebuilt documentation out.

I didn't upload it because the reverse deps situation wasn't perfect:

- liquidsoap has an unsatisfied libogg-ocaml-dev dep) -- unrelated
breakage ;

- why3 is broken (looks for non-existing graph.cmo at some point) --
unrelated breakage ;

- alt-ergo and ocaml-atd are broken with the following message:
Error: the code back-end requires the type of every nonterminal symbol
to be
known. Please specify the type of every symbol via %type declarations,
or
enable type inference (look up --infer in the manual).
Type inference is automatically enabled when Menhir is used via Dune,
provided the dune-project file says (using menhir 2.0) or later.
The types of the following nonterminal symbols are unknown:
<long list>

And for those two, the problem only appears with the new menhir
package, so there's something to be done.

I'm looking into it but wanted to let people know where things stood.

Cheers,

J.Puydt