net/asterisk22: Update 20.16.0 → 20.17.0

Changelog:
https://downloads.asterisk.org/pub/telephony/asterisk/releases/ChangeLog-20.17.0.html

Add non-default option UNBOUND to prevent silent grab of libunbound.so
from dns/unbound.

PR: 291176
Sponsored by: FLEX-IT LLC
Co-authored-by: Vladimir Druzenko <vvd@FreeBSD.org>