edns: fixed nsid, dig corrupted memory, bad memory reservation

src/knot/nameserver/internet.c

src/knot/nameserver/process_query.c

src/knot/nameserver/process_query.h

src/knot/server/server.c

src/knot/server/server.h

src/libknot/edns.c

src/libknot/edns.h

src/libknot/packet/pkt.c

src/libknot/packet/pkt.h

src/utils/dig/dig_exec.c

tests/edns.c

tests/fake_server.h

tests/pkt.c