My patch won't apply, since I ran into this while attempting a backport. Sorry about that. Still, the solution is simple enough: add pkg-config to the dependency list of xtables-addons-source.
-- John Wright <j...@debian.org> -- To UNSUBSCRIBE, email to debian-bugs-rc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org