Fix unused code warnings.

Author: tnull

lightning/src/util/fairrwlock.rs

@@ -17,6 +17,7 @@ pub struct FairRwLock<T> {
 	waiting_writers: AtomicUsize,
 }
 
+#[cfg_attr(test, allow(dead_code))]
 impl<T> FairRwLock<T> {
 	pub fn new(t: T) -> Self {
 		Self { lock: RwLock::new(t), waiting_writers: AtomicUsize::new(0) }
@@ -32,6 +33,7 @@ impl<T> FairRwLock<T> {
 		res
 	}
 
+	#[allow(dead_code)]
 	pub fn try_write(&self) -> TryLockResult<RwLockWriteGuard<T>> {
 		self.lock.try_write()
 	}

lightning/src/util/test_utils.rs

@@ -267,12 +267,12 @@ impl TestChannelMessageHandler {
 		expected_msgs.as_mut().unwrap().push(ev);
 	}
 
-	fn received_msg(&self, ev: wire::Message<()>) {
+	fn received_msg(&self, _ev: wire::Message<()>) {
 		let mut msgs = self.expected_recv_msgs.lock().unwrap();
 		if msgs.is_none() { return; }
 		assert!(!msgs.as_ref().unwrap().is_empty(), "Received message when we weren't expecting one");
 		#[cfg(test)]
-		assert_eq!(msgs.as_ref().unwrap()[0], ev);
+		assert_eq!(msgs.as_ref().unwrap()[0], _ev);
 		msgs.as_mut().unwrap().remove(0);
 	}
 }