net/nmap is broken

[John Klos <john%klos.com@localhost>]

FYI: net/nmap is failing with:

c++ -c -I./liblinear -Ino/include -DNOLUA -I./libdnet-stripped/include -I/usr/local/include -I/usr/local/include -I/usr/include -I/usr/local/include -I/usr/include -I/usr/include -I./nbase -I./nsock/include -DHAVE_CONFIG_H -DNMAP_PLATFORM=\"x86_64--netbsd\" -DNMAPDATADIR=\"/usr/local/share/nmap\" -D_FORTIFY_SOURCE=2 -O2 -I/usr/local/include -I/usr/include -Wall -fno-strict-aliasing   traceroute.cc -o traceroute.o
traceroute.cc: In function 'bool parse_encapsulated_reply(const u8*, unsigned int, Reply*)':
traceroute.cc:1084:24: error: expected primary-expression before 'struct'
 1084 |     if (len < offsetof(struct icmp, icmp_id) + 2)
      |                        ^~~~~~
In file included from struct_ip.h:56,
                 from traceroute.cc:113:
traceroute.cc:1084:37: error: 'icmp_hun' was not declared in this scope; did you mean 'icmp_hdr'?
 1084 |     if (len < offsetof(struct icmp, icmp_id) + 2)
      |                                     ^~~~~~~
traceroute.cc:1084:15: error: 'offsetof' was not declared in this scope
 1084 |     if (len < offsetof(struct icmp, icmp_id) + 2)
      |               ^~~~~~~~
traceroute.cc:125:1: note: 'offsetof' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?
  124 | #include <set>
  +++ |+#include <cstddef>
  125 | #include <vector>
traceroute.cc:1091:52: error: expected primary-expression before 'struct'
 1091 |     if (len < sizeof(struct icmpv6_hdr) + offsetof(struct icmpv6_msg_echo, icmpv6_seq) + 2)
      |                                                    ^~~~~~
traceroute.cc:1091:76: error: 'icmpv6_seq' was not declared in this scope; did you mean 'icmp_seq'?
 1091 |     if (len < sizeof(struct icmpv6_hdr) + offsetof(struct icmpv6_msg_echo, icmpv6_seq) + 2)
      |                                                                            ^~~~~~~~~~
      |                                                                            icmp_seq
traceroute.cc:1091:43: error: 'offsetof' was not declared in this scope
 1091 |     if (len < sizeof(struct icmpv6_hdr) + offsetof(struct icmpv6_msg_echo, icmpv6_seq) + 2)
      |                                           ^~~~~~~~
traceroute.cc:1091:43: note: 'offsetof' is defined in header '<cstddef>'; did you forget to '#include <cstddef>'?

John