f clarify new assertion var text a bit

Author: TheBlueMatt

lightning/src/routing/router.rs

@@ -1785,9 +1785,9 @@ struct PathBuildingHop<'a> {
 	/// avoid processing them again.
 	was_processed: bool,
 	/// If we've already processed a channel backwards from a target node, we shouldn't update our
-	/// selected best path to that node. This should never happen, but with multiple codepaths
-	/// processing channels we've had issues here in the past, so in debug-mode we track it and
-	/// assert on it when processing a node.
+	/// selected best path from that node to the destination. This should never happen, but with
+	/// multiple codepaths processing channels we've had issues here in the past, so in debug-mode
+	/// we track it and assert on it when processing a node.
 	#[cfg(all(not(ldk_bench), any(test, fuzzing)))]
 	best_path_from_hop_selected: bool,
 	/// When processing a node as the next best-score candidate, we want to quickly check if it is