Zstd compression in pure OCaml

fix mlxxhash

+1 -1
+1 -1
src/dune
··· 2 2 (name zstd) 3 3 (public_name zstd) 4 4 (modules zstd zstd_encode zstd_decode fse constants bit_writer bit_reader huffman) 5 - (libraries xxhash bitstream) 5 + (libraries mlxxhash bitstream) 6 6 (ocamlopt_flags (:standard -O3)))