[MacPorts] #59429: ocaml: Update to 4.09.0 and fix livecheck

[MacPorts]

#59429: ocaml: Update to 4.09.0 and fix livecheck
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  Reporter:  ryandesign  |      Owner:  pmetzger
      Type:  update      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  ocaml       |
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Comment (by pmetzger):

 We should be able to update lablgtk2 to the latest without updating ocaml
 to 4.09 yet; the opam file indicates it will work with any ocaml after
 4.05.

 BTW, among other big breaking changes: camlp4 no longer will work with
 4.09; 4.08 is the last version that supports it. So we need to update
 anything in tree that requires camlp4 before we update to 4.09. It would
 probably also be for the best to update coq (which I've been neglecting
 for a while) because the latest version no longer needs camlp5 etc.; my
 suspicion is that we can no longer rely on the camlp5 maintainers to keep
 that going either.

 I'm happy to work with you to do the necessary steps, or you can just
 needle me until I've gotten them done.

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Ticket URL: <https://trac.macports.org/ticket/59429#comment:4>
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