gnu: ocaml-bitstring: Use dune-build-system.

* gnu/packages/ocaml.scm (ocaml-bitstring): Use dune-build-system.
(ocaml4.02-bitstring)[build-system]: Use ocaml-build-system explicitly.

gnu/packages/ocaml.scm

@@ -1615,31 +1615,19 @@ ocaml-migrate-parsetree")
               (sha256
                (base32
                 "15jjk2pq1vx311gl49s5ag6x5y0654x35w75z07g7kr2q334hqps"))))
-    (build-system ocaml-build-system)
+    (build-system dune-build-system)
     (native-inputs
      `(("camlp4" ,camlp4)
        ("time" ,time)
        ("autoconf" ,autoconf)
        ("automake" ,automake)
-       ("bisect" ,ocaml-bisect)
+       ("bisect" ,ocaml-bisect)))
-       ("dune" ,dune)))
     (propagated-inputs
      `(("camlp4" ,camlp4)
        ("ocaml-ppx-tools-versioned" ,ocaml-ppx-tools-versioned)))
     (arguments
      `(#:tests? #f; Tests fail to build
-       #:phases
+       #:jbuild? #t))
-       (modify-phases %standard-phases
-         (delete 'configure)
-         (replace 'build
-           (lambda _
-             (invoke "jbuilder" "build" "@install")
-             #t))
-         (replace 'install
-           (lambda* (#:key outputs #:allow-other-keys)
-             (invoke "dune" "install"
-                     "--prefix" (assoc-ref outputs "out"))
-             #t)))))
     (properties
       `((ocaml4.02-variant . ,(delay ocaml4.02-bitstring))))
     (home-page "https://github.com/xguerin/bitstring")
@@ -1665,6 +1653,7 @@ powerful.")
                  (base32
                   "0vy8ibrxccii1jbsk5q6yh1kxjigqvi7lhhcmizvd5gfhf7mfyc8"))
                 (patches (search-patches "ocaml-bitstring-fix-configure.patch"))))
+      (build-system ocaml-build-system)
       (arguments
        `(#:ocaml ,ocaml-4.02
          #:findlib ,ocaml4.02-findlib