cad/pcb-rnd: Update 3.1.6 => 3.1.7b, take maintainership

[alven]

Summary

Maintainer wasn't active for the last 2 years.

News:

• http://www.repo.hu/projects/pcb-rnd/news.html

Release notes:

• http://www.repo.hu/projects/pcb-rnd/releases/relnotes-3.1.7.txt
• http://www.repo.hu/projects/pcb-rnd/releases/relnotes-3.1.7b.txt

Changelogs:

• http://www.repo.hu/projects/pcb-rnd/releases/changelog-3.1.7.txt
• http://www.repo.hu/projects/pcb-rnd/releases/changelog-3.1.7b.txt

• Make DOCS option really work
• Pet portclippy(1) and portfmt(1)

Test Plan

For every {amd64, i386} × {14.3, 13.5}:

• Successful poudriere testport
• Successful run-testing

[alven]

OPTIONS_SUB isn't needed when PORTDOCS=*

[yuri]

Approved.

Thanks,
Yuri