zones: migrate to new logging API

src/knot/dnssec/zone-events.c

src/knot/dnssec/zone-keys.c

src/knot/server/journal.c

src/knot/updates/ddns.c

src/knot/zone/contents.c

src/knot/zone/events.c

src/knot/zone/zone-load.c

src/knot/zone/zone.c

src/knot/zone/zonedb-load.c