Reduce log severity of onion failures and log CLN bug 5154.

Author: TheBlueMatt

lightning/src/ln/onion_utils.rs

@@ -434,6 +434,8 @@ pub(super) fn process_onion_failure<T: secp256k1::Signing, L: Deref>(secp_ctx: &
 											// short channel id.
 											if failing_route_hop.short_channel_id == chan_update.contents.short_channel_id {
 												short_channel_id = Some(failing_route_hop.short_channel_id);
+											} else {
+												log_info!(logger, "Node provided a channel_update for which it was not authoritative, likely a busted CLN node - https://github.com/ElementsProject/lightning/issues/5154");
 											}
 											network_update = Some(NetworkUpdate::ChannelUpdateMessage {
 												msg: chan_update,
@@ -478,10 +480,10 @@ pub(super) fn process_onion_failure<T: secp256k1::Signing, L: Deref>(secp_ctx: &
 
 						let (description, title) = errors::get_onion_error_description(error_code);
 						if debug_field_size > 0 && err_packet.failuremsg.len() >= 4 + debug_field_size {
-							log_warn!(logger, "Onion Error[from {}: {}({:#x}) {}({})] {}", route_hop.pubkey, title, error_code, debug_field, log_bytes!(&err_packet.failuremsg[4..4+debug_field_size]), description);
+							log_info!(logger, "Onion Error[from {}: {}({:#x}) {}({})] {}", route_hop.pubkey, title, error_code, debug_field, log_bytes!(&err_packet.failuremsg[4..4+debug_field_size]), description);
 						}
 						else {
-							log_warn!(logger, "Onion Error[from {}: {}({:#x})] {}", route_hop.pubkey, title, error_code, description);
+							log_info!(logger, "Onion Error[from {}: {}({:#x})] {}", route_hop.pubkey, title, error_code, description);
 						}
 					} else {
 						// Useless packet that we can't use but it passed HMAC, so it