build bcachefs-tools for ubuntu 16.04

  wget http://archive.ubuntu.com/ubuntu/pool/universe/b/bcachefs-tools/bcachefs-tools_24.orig.tar.gz

 wget http://archive.ubuntu.com/ubuntu/pool/main/k/keyutils/libkeyutils1_1.6-6ubuntu1_amd64.deb

 wget http://archive.ubuntu.com/ubuntu/pool/main/k/keyutils/libkeyutils-dev_1.6-6ubuntu1_amd64.deb

 wget http://archive.ubuntu.com/ubuntu/pool/main/libz/libzstd/libzstd_1.5.5+dfsg2.orig.tar.xz