Fixed usages of modified node API

src/dnslib/node.c

src/dnslib/response.c

src/dnslib/response2.c

src/dnslib/tests/dnslib/node_tests.c

src/dnslib/zone-contents.c

src/dnslib/zone-dump.c

src/dnslib/zone-load.c

src/dnslib/zone-tree.c

src/knot/server/name-server.c

src/knot/server/xfr-in.c

src/zcompile/zcompile.c

src/zcompile/zparser.y