security/softether-devel: update to v4.27-9668-beta
As security/softether and -devel are created and maintained by different
people for a long time, there was a lot of difference between and no
consistency between both ports.
I grab both ports and renew this port based on security/softether. Now
there're least differences such as VERSION, COMMENT, CONFLICTS between
both. To make both ports consistent, I quit fetching from GitHub. Using
upstream site[1] instead. Upstream distributes -rtm and -beta suffixed
tarballs. -rtm corresponds to security/softether, -beta does to
security/softether-devel now.
[1] https://www.softether-download.com/
Approved by: mentors (implicit)