Use wire context where appropriate

src/knot/dnssec/nsec3-chain.c

src/knot/dnssec/rrset-sign.c

src/knot/zone/timers.c

src/libknot/packet/pkt.c

src/libknot/packet/rrset-wire.c

src/libknot/rrset-dump.c

src/libknot/rrtype/opt.c

src/libknot/rrtype/tsig.c

src/utils/common/exec.c