Apparently the ${HOME} variable is set to the filesystem root "/" in
Cirrus CI FreeBSD instances. Just create an installation directory
without it, then.
While here, set --pkgconfigdir to closely mimick the build in the
FreeBSD ports tree.
When the github application Cirrus CI (https://cirrus-ci.org/) is
installed, this build description file adds FreeBSD build checks to
changes and PRs in github.
There are four build tasks currently, a minimal build and one with all
options enabled on two different FreeBSD versions.
Florian Walpen
falkTX