Add some tests for sbin/ndp binary

[lytboris_gmail.com]

Summary

This differential adds some tests for ndp binary including a test requested in https://reviews.freebsd.org/D49459

Test Plan

kyua test -k /usr/tests/sys/netinet/Kyuafile ndp

Expected output:

ndp:dad  ->  passed  [5.022s]
ndp:ndp_add_gu_success  ->  passed  [1.537s]
ndp:ndp_del_gu_success  ->  passed  [2.464s]
ndp:ndp_lookup_host  ->  passed  [0.874s]
ndp:ndp_slaac_default_route  ->  passed  [2.473s]
ndp:static_temporary  ->  passed  [0.570s]

Results file id is usr_tests_sys_netinet.20251023-133830-739277
Results saved to /home/..../.kyua/store/results.usr_tests_sys_netinet.20251023-133830-739277.db

6/6 passed (0 broken, 0 failed, 0 skipped)

[glebius]

Thanks for the work, Boris! Do you have a public git repo where I would be able to pull commits from to push them to FreeBSD?

tests/sys/netinet/ndp.sh

197 ↗

(On Diff #164883)

Making this comment without any knowledge of DAD or NDP. One thing I learned writing the tests. Large sleep times are not appreciated due to increasing CI run times. Small sleep times are making tests flaky. Is it possible to substitute all sleep 5 in this test with a loop that checks for a certain condition and sleeps for 0.01?

[lytboris_gmail.com]

Is it possible to substitute all sleep 5 in this test with a loop

Reworked diff to get rid of long sleeps, now all NDP-related tests wait for DAD to finish in wait_tentative()

Do you have a public git repo where I would be able to pull commits from to push them to FreeBSD?

I can make a personal fork on github.com if that counts.