Fix bug9309, and n_noncanonical count/continue code

When we moved channel_matches_target_addr_for_extend() into a separate
function, its sense was inverted from what one might expect, and we
didn't have a ! in one place where we should have.

Found by skruffy.
Avoid assertion failure on unexepcted address family in DNS reply.

Fixes bug 9337; bugfix on 0.2.4.7-alpha.
Merge branch 'bug9337' into maint-0.2.4
Merge branch 'maint-0.2.4' into release-0.2.4