lang/ocaml: fix packaging on armv6

pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.a:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.cma:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.cmi:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.cmx:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.cmxa:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.cmxs:No such file or directory
pkg-static: Unable to access file /wrkdirs/usr/ports/lang/ocaml/work/stage/usr/local/lib/ocaml/raw_spacetime_lib.mli:No such file or directory