chan_iax2: Reload of iax peer results in loss of host address/port

When using a non-dynamic peer address, build_peer() invalidates the
peer address structure by setting the address family to unspecified.
However, if dnsmgr is enabled, the subsequent call to ast_dnsmgr_lookup()
will not amend the peer address if the cache is still valid, resulting
in peer connectivity failures.
To fix this, we call ast_dnsmgr_refresh() instead.

ASTERISK-26865

Change-Id: Id8a89a2f771ebbaf32255a35fe596a6dcb97a082

channels/chan_iax2.c

@@ -12909,7 +12909,13 @@ static struct iax2_peer *build_peer(const char *name, struct ast_variable *v, st
 					/* Non-dynamic.  Make sure we become that way if we're not */
 					AST_SCHED_DEL(sched, peer->expire);
 					ast_clear_flag64(peer, IAX_DYNAMIC);
-					peer->addr.ss.ss_family = AST_AF_UNSPEC;
+					if (peer->dnsmgr) {
+						// Make sure we refresh dnsmgr if we're using it
+						ast_dnsmgr_refresh(peer->dnsmgr);
+					} else {
+						// Or just invalidate the address
+						peer->addr.ss.ss_family = AST_AF_UNSPEC;
+					}
 					if (ast_dnsmgr_lookup(v->value, &peer->addr, &peer->dnsmgr, srvlookup ? "_iax._udp" : NULL)) {
 						return peer_unref(peer);
 					}