feat: add crossbeam_n_parking_lot

__concurrent/crossbeam_n_parking_lot/src/main.rs

@@ -0,0 +1,16 @@
+use crossbeam_channel::unbounded;
+// use lock_api::Mutex;
+// use std::sync::Arc;
+use std::thread;
+
+fn main() {
+    // let lock = Arc::new(Mutex::new::<RawSpinlock, i32>(0_i32));
+    let (s, r) = unbounded::<i32>();
+
+    thread::spawn(move || {
+        s.send(1).unwrap();
+    });
+
+    let x = r.recv().unwrap();
+    println!("Received: {}", x);
+}