perf(net): improve overall multiplex performance for rlpx satellite stream

[hoank101]

Closes #13856

[mattsse]

cool, thanks for picking this up.

this already looks good.

still have some nits, and we can now remove the poll_ready + send calls from the stream impl entirely

[hoank101]

thank @mattsse for review, i just updated

[hoank101]

also help me review this PR @mattsse

[mattsse]

no that we do this on the sink impl, we can remove

reth/crates/net/eth-wire/src/multiplex.rs

Lines 469 to 493 in cd44fc3

	loop {
	match this.inner.conn.poll_ready_unpin(cx) {
	Poll::Ready(Ok(())) => {
	if let Some(msg) = this.inner.out_buffer.pop_front() {
	if let Err(err) = this.inner.conn.start_send_unpin(msg) {
	return Poll::Ready(Some(Err(err.into())))
	}
	} else {
	break
	}
	}
	Poll::Ready(Err(err)) => {
	if let Err(disconnect_err) =
	this.inner.conn.start_disconnect(DisconnectReason::DisconnectRequested)
	{
	return Poll::Ready(Some(Err(disconnect_err.into())))
	}
	return Poll::Ready(Some(Err(err.into())))
	}
	Poll::Pending => {
	conn_ready = false;
	break
	}
	}
	}

[hoank101]

seem look good, please help me review @mattsse