channel: move inflight + feerate methods to channel.c

Need these more accessible for next patch, which moves the next_feerate
info into listpeers

lightningd/channel.c

@@ -715,6 +715,29 @@ void channel_fail_forget(struct channel *channel, const char *fmt, ...)
 	tal_free(why);
 }
 
+struct channel_inflight *
+channel_current_inflight(const struct channel *channel)
+{
+	struct channel_inflight *inflight;
+	/* The last inflight should always be the one in progress */
+	inflight = list_tail(&channel->inflights,
+			     struct channel_inflight,
+			     list);
+	if (inflight)
+		assert(bitcoin_txid_eq(&channel->funding_txid,
+				       &inflight->funding->txid));
+	return inflight;
+}
+
+u32 channel_last_funding_feerate(const struct channel *channel)
+{
+	struct channel_inflight *inflight;
+	inflight = channel_current_inflight(channel);
+	if (!inflight)
+		return 0;
+	return inflight->funding->feerate;
+}
+
 void channel_internal_error(struct channel *channel, const char *fmt, ...)
 {
 	va_list ap;

lightningd/channel.h

@@ -286,6 +286,13 @@ new_inflight(struct channel *channel,
 struct channel_inflight *channel_inflight_find(struct channel *channel,
 					       const struct bitcoin_txid *txid);
 
+/* What's the most recent inflight for this channel? */
+struct channel_inflight *
+channel_current_inflight(const struct channel *channel);
+
+/* What's the last feerate used for a funding tx on this channel? */
+u32 channel_last_funding_feerate(const struct channel *channel);
+
 void delete_channel(struct channel *channel STEALS);
 
 const char *channel_state_name(const struct channel *channel);

lightningd/dual_open_control.c

@@ -119,21 +119,6 @@ void json_add_unsaved_channel(struct json_stream *response,
 	json_object_end(response);
 }
 
-
-static struct channel_inflight *
-channel_current_inflight(struct channel *channel)
-{
-	struct channel_inflight *inflight;
-	/* The last inflight should always be the one in progress */
-	inflight = list_tail(&channel->inflights,
-			     struct channel_inflight,
-			     list);
-	if (inflight)
-		assert(bitcoin_txid_eq(&channel->funding_txid,
-				       &inflight->funding->txid));
-	return inflight;
-}
-
 static void handle_signed_psbt(struct lightningd *ld,
 			       struct subd *dualopend,
 			       const struct wally_psbt *psbt,