daemon: keep enum htlc_state within struct htlc.

And update the state as HTLCs get moved around.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

daemon/peer.h

@@ -97,6 +97,7 @@ struct peer_visible_state {
 	/* cstate to generate next commitment tx. */
 	struct channel_state *staging_cstate;
 
+	/* FIXME: Use single map in struct peer. */
 	/* HTLCs offered by this side */
 	struct htlc_map htlcs;
 };