The Apcon has a 768-bit host key and newer versions of OpenSSH refuse
to talk to anything with less than a 1024-bit host key. So until we
figure out if we can make a new host key on the Apcon, with or without
new firmware, we are going to use a "special" version of ssh for
talking to it. This is an old, statically-linked version of OpenSSH 7.5.