MyRocks is not present in non-old-systemd tarballs

I am looking at the three 64-bit binary tarballs that we ship:

mariadb-10.2.12-linux-glibc_214-x86_64.tar.gz

mariadb-10.2.12-linux-systemd-x86_64.tar.gz

mariadb-10.2.12-linux-x86_64.tar.gz

Of these three, only mariadb-10.2.12-linux-systemd-x86_64 has lib/plugin/ha_rocksdb.so in it.

This is odd, because "systemd" binary is not "a binary with systemd for modern OSes", it is "a binary for OSes with older version of systemd".

This "systemd" binary is unusable on modern OSes like latest LTS Ubuntu or latest non-LTS ubuntu, check out MDEV-12370 for details. (An example of a recent OS where it is usable: latest CentOS, 7.x)

For comparison, Percona-Server-5.7.20-19-Linux.x86_64.ssl100.tar.gz does not depend on out-of-date systemd and also has ha_rocksdb.so in it.