examples: fix `cargo clippy --examples` reports
diff --git a/examples/vicodec_pipeline/encoder.rs b/examples/vicodec_pipeline/encoder.rs
index 0936a87..1565b34 100644
--- a/examples/vicodec_pipeline/encoder.rs
+++ b/examples/vicodec_pipeline/encoder.rs
@@ -1,6 +1,5 @@
 pub mod client;
 
-use v4l2;
 use v4l2::device::queue::{direction, dqbuf, qbuf, states, FormatBuilder, Queue};
 use v4l2::device::{Device, DeviceConfig};
 use v4l2::ioctl::FormatFlags;
@@ -13,7 +12,6 @@
 use std::sync::mpsc::{self, channel, Receiver, Sender};
 use std::sync::{Arc, Mutex};
 
-use anyhow;
 use thiserror::Error;
 
 #[derive(Debug, PartialEq)]
@@ -104,17 +102,19 @@
         let output_queue = Queue::get_output_mplane_queue(device.clone())?;
 
         // On an encoder, the OUTPUT formats are not compressed...
-        if let None = output_queue
+        if output_queue
             .format_iter()
             .find(|fmt| !fmt.flags.contains(FormatFlags::COMPRESSED))
+            .is_none()
         {
             panic!("This is not an encoder: input formats are not raw.");
         }
 
         // But the CAPTURE ones are.
-        if let None = capture_queue
+        if capture_queue
             .format_iter()
             .find(|fmt| fmt.flags.contains(FormatFlags::COMPRESSED))
+            .is_none()
         {
             panic!("This is not an encoder: output formats are not compressed.");
         }
diff --git a/examples/vicodec_pipeline/encoder/client.rs b/examples/vicodec_pipeline/encoder/client.rs
index 75db383..7c31db9 100644
--- a/examples/vicodec_pipeline/encoder/client.rs
+++ b/examples/vicodec_pipeline/encoder/client.rs
@@ -62,7 +62,7 @@
 
 impl Client {
     fn send(&self, command: Command) -> SendResult<()> {
-        if let Err(_) = self.send.send(command) {
+        if self.send.send(command).is_err() {
             return Err(SendError::ChannelSendError);
         }
         if let Err(e) = self.waker.wake() {
diff --git a/examples/vicodec_pipeline/main.rs b/examples/vicodec_pipeline/main.rs
index 498ea96..e7e304a 100644
--- a/examples/vicodec_pipeline/main.rs
+++ b/examples/vicodec_pipeline/main.rs
@@ -5,7 +5,6 @@
 use encoder::*;
 use framegen::FrameGenerator;
 
-use ctrlc;
 use std::io::{self, Write};
 use std::path::Path;
 use std::sync::atomic::{AtomicBool, Ordering};
@@ -118,7 +117,7 @@
     use std::collections::VecDeque;
 
     let mut free_buffers = VecDeque::new();
-    for _ in 0..NUM_BUFFERS + 0 {
+    for _ in 0..NUM_BUFFERS {
         free_buffers.push_back(vec![0u8; output_format.plane_fmt[0].sizeimage as usize]);
     }
 
diff --git a/examples/vicodec_test/ioctl_api.rs b/examples/vicodec_test/ioctl_api.rs
index 3317733..0f375f2 100644
--- a/examples/vicodec_test/ioctl_api.rs
+++ b/examples/vicodec_test/ioctl_api.rs
@@ -151,8 +151,8 @@
         .collect();
 
     // Start streaming.
-    streamon(&mut fd, output_queue).expect("Failed to start output queue");
-    streamon(&mut fd, capture_queue).expect("Failed to start capture queue");
+    streamon(&fd, output_queue).expect("Failed to start output queue");
+    streamon(&fd, capture_queue).expect("Failed to start capture queue");
 
     let mut cpt = 0usize;
     let mut total_size = 0usize;
@@ -227,8 +227,8 @@
     }
 
     // Stop streaming.
-    streamoff(&mut fd, capture_queue).expect("Failed to stop capture queue");
-    streamoff(&mut fd, output_queue).expect("Failed to stop output queue");
+    streamoff(&fd, capture_queue).expect("Failed to stop capture queue");
+    streamoff(&fd, output_queue).expect("Failed to stop output queue");
 
     // Clear the mappings
     drop(capture_mappings);