pimd: Close AutoRP socket when not needed (backport #17934)

[mergify]

Don't leave the socket open if we are not enabled for discovery or announcements.
Properly disable autorp discovery by setting false rather than nb destroy.

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This is an automatic backport of pull request #17934 done by Mergify.

[mergify]

Cherry-pick of 5d102a0 has failed:

On branch mergify/bp/stable/10.2/pr-17934
Your branch is up to date with 'origin/stable/10.2'.

You are currently cherry-picking commit 5d102a0a7.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   pimd/pim_cmd_common.c

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   pimd/pim_autorp.c

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally