Log Message:
s6-dns: update to 2.4.0.0. Changes:

- This is a major update because a function was factorized in
  skalibs, and the libs6dns implementation
  (s6dns_minineststring_read()) was removed.
- A new function, s6dns_engine_query(), was also added.
- Higher debug levels in s6-dnsq and s6-dnsqr can now dump
  received packets.