message: transport: Clarify a comment
diff: @@ -17,7 +17,7 @@ pub trait Sendable: Debug {
  /// Enqueue data to send on the stream. Returns bytes enqueued.
  fn send(&mut self, buf: &[u8]) -> Res<usize>;
  - /// If enqueueing some data with send will return nonzero.
  + /// If attempting to enqueue some data with send() will return nonzero.
  fn send_data_ready(&self) -> bool;
  /// Close the stream. Enqueued data will be sent.
  