reduce duplication inside portable lock directories

[Alizter]

Here is the portable lock directory for the relocatable compiler:

Details

(version 5.4.1.20251109.1)

(install
 (all_platforms
  (withenv
   ((= MSYS2_ARG_CONV_EXCL *)
    (= LSAN_OPTIONS detect_leaks=0,exitcode=0)
    (= ASAN_OPTIONS detect_leaks=0,exitcode=0))
   (run
    sh
    process.sh
    %{make}
    install
    %{pkg-self:build-id}
    %{pkg-self:name}
    %{prefix}))))

(build
 (choice
  ((((arch x86_64)
     (os linux))
    ((arch arm64)
     (os linux)))
   ((action
     (withenv
      ((= MSYS2_ARG_CONV_EXCL *)
       (= LSAN_OPTIONS detect_leaks=0,exitcode=0)
       (= ASAN_OPTIONS detect_leaks=0,exitcode=0))
      (run
       sh
       process.sh
       %{make}
       -j%{jobs}
       %{pkg-self:build-id}
       %{pkg-self:name}
       %{pkg:compiler-cloning:version}
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       --prefix=%{prefix}
       --docdir=%{doc}/ocaml
       --with-relative-libdir=../lib/ocaml
       --with-stublibs=../stublibs
       --enable-runtime-search=always
       --enable-runtime-search-target
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       --disable-warn-error)))))
  ((((arch x86_64)
     (os macos))
    ((arch arm64)
     (os macos)))
   ((action
     (withenv
      ((= MSYS2_ARG_CONV_EXCL *)
       (= LSAN_OPTIONS detect_leaks=0,exitcode=0)
       (= ASAN_OPTIONS detect_leaks=0,exitcode=0))
      (run
       sh
       process.sh
       %{make}
       -j%{jobs}
       %{pkg-self:build-id}
       %{pkg-self:name}
       %{pkg:compiler-cloning:version}
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       --prefix=%{prefix}
       --docdir=%{doc}/ocaml
       --with-relative-libdir=../lib/ocaml
       --with-stublibs=../stublibs
       --enable-runtime-search=always
       --enable-runtime-search-target
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       CC=cc
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       (when false "")
       --disable-warn-error)))))))

(depends
 (all_platforms (compiler-cloning)))

(source
 (fetch
  (url
   https://github.com/dra27/ocaml/archive/b74c645ef30c6060dcc293a73811a9ae9ceefd57.tar.gz)
  (checksum
   sha256=b461d60f5b542bbd3315d3d984efaef9113d1672b5f6bfdd46efd5e96060d17a)))

(extra_sources
 (process.sh
  (fetch
   (url
    https://raw.githubusercontent.com/dra27/ocaml/55ce12b0f197b9a7a0165310b131052951f98a02/tools/opam/process.sh)
   (checksum
    sha256=b2febe05d19e07db4881ef11cf8769c31226f32305ad10ea13b0a2262835d914))))

There is entire duplication between the build plan for macos and linux, even though they only differ at a single point. We should remove the duplication.

The (when false "") expressions are something else that should be simplified too.