sysutils/logwatch: Update 7.12 => 7.13

Commmit log:
https://sourceforge.net/p/logwatch/git/ci/88df91d67696495e2d3eb0bc18736da50bba2fb0/log/

• Use /var/cache/logwatch instead of /usr/local/var/logwatch
• Add files/pkg-message.in for latest important changes.
• Refresh patches.

PR: 288385