pkgbase: Do not record dependency on non-existent libcompat package

libcompat only provides a .a which is put in the -dev package.
Add a special record for it so we do not require a dependency on the
non-existent package FreeBSD-libcompat.

Sponsored by: Beckhoff Automation GmbH & Co. KG

(cherry picked from commit 5391bcf0f7e4f9021b56d050cbd798940858d9c0)