bytestream-socks5: stop using _conn_send_with_reply
bytestream-socks5: stop using _conn_send_with_reply

This makes it clearer that gabble_bytestream_socks5_initiate() can only
fail synchronously for local reasons.
_gabble_connection_send_with_reply() only returns FALSE if we have no
porter; but from the moment we go to state CONNECTED (before which you
can't request channels) to the moment the connection is disconnected, we
do have a porter.

Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble