net/olsrd:

• Update to 0.9.8
• Switch to fetch from GitHub because they don't provide tarballs anymore
• Fix portlint warnings
• Fix some GNUisms (cp -t)
• Fix compile error when RTF_CLONING is not defined

PR: 240563
Submitted by: myself
Approved by: Nikola Kolev <koue@chaosophia.net> (maintainer)
MFH: 2019Q4