message: simplify count function
diff: @@ -20,10 +20,7 @@ impl<S: Syscalls> Leds<S> {
  /// that the driver is working, as it may still fail to allocate grant
  /// memory.
  pub fn count() -> Option<u32> {
  - S::command(DRIVER_ID, LEDS_COUNT, 0, 0)
  - .get_success_u32()
  - .map(|leds_count| Some(leds_count))
  - .unwrap_or(None)
  + S::command(DRIVER_ID, LEDS_COUNT, 0, 0).get_success_u32()
  }
  pub fn on(led: u32) {
  