comms/direwolf: Update 1.8 => 1.8.1

Changelogs:

• https://github.com/wb2osz/direwolf/releases/tag/1.8.1
• https://github.com/wb2osz/direwolf/compare/1.8...1.8.1

Approved by: hamradio@ (alven@, yuri@)
Approved by: yuri@ (maintainer, Mentor)
Differential Revision: https://reviews.freebsd.org/D54299