This not a qustion, rather an answer.
Today DragonflyBSD was installed.
After the installation, pkg update was done,
and well known bug from the post title emarged.
Recommended fix:
cp /usr/local/etc/pkg/repos/df-latest.conf.sample /usr/local/etc/pkg/repos/df-latest.conf
didn't solve a problem.
After reading some pkg related man pages,
the solution was to edit df-latest.conf,
and change first Avalon block to:
Avalon: {
url : http://mirror-master.dragonflybsd.org/dports/${ABI}/LATEST
mirror_type : HTTP
enabled : yes
}
If somenone wants to try dfbsd, I will be happy if this helps.