fixup! ctl: implemented multi-threaded (mutexted) CTL handling

distro/pkg/deb/libknot15.symbols

src/knot/ctl/commands.c

src/knot/events/handlers/backup.c

src/knot/events/replan.c

src/knot/server/server.c

src/knot/zone/zone.h

src/libknot/control/control.h