Log Message:
various fixes including support for netbsd-10.

- move the "don't know picking 1.6" match to be "1.*" from \ 
"1*".
- add 9.99.10[45678], netbsd 9.99, netbsd 10, and netbsd 10.99
  support to configure match.
- make netbsd 10.x the "i don't know default" now.
- port the netbsd dsock.c code to the merged inpcb code since
  http://mail-index.netbsd.org/source-changes/2022/10/28/msg141800.html

i haven't bumped the pkg because nothing really changed for the
pre-9.99.104 systems, and 9.99.104 and newer haven't built since.