f add note about timeout

Author: TheBlueMatt

lightning/src/ln/channelmanager.rs

@@ -451,7 +451,7 @@ pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref,
 	/// Storage for PaymentSecrets and any requirements on future inbound payments before we will
 	/// expose them to users via a PaymentReceived event. HTLCs which do not meet the requirements
 	/// here are failed when we process them as pending-forwardable-HTLCs, and entries are removed
-	/// after we generate a PaymentReceived upon receipt of all MPP parts.
+	/// after we generate a PaymentReceived upon receipt of all MPP parts or when they time out.
 	/// Locked *after* channel_state.
 	pending_inbound_payments: Mutex<HashMap<PaymentHash, PendingInboundPayment>>,