This encoding scheme is no longer just used for short_channel_ids, so make
the names more generic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The only real change is dump_gossip() used to call
maybe_create_next_scid_reply(), but now I've simply renamed
that to maybe_send_query_responses() and we call it directly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>