Make geoip use channel_is_client so it ignores flapping relays

In channel_do_open_actions(), we probably want to use channel_is_client() rather than connection_or_digest_is_known_relay().

    /* only report it to the geoip module if it's not a known router */
    if (!connection_or_digest_is_known_relay(chan->identity_digest)) {
      if (channel_get_addr_if_possible(chan, &remote_addr)) {

Bugfix on legacy/trac#23533 (moved), 0.3.0.1-alpha.

We should make sure legacy/trac#24898 (moved) is fixed in any version we backport this to.