misc: Automatically fix cargo clippy issues added in 1.65 (stable)

The code of the stable branch diverges from the main branch, so we
can't directly backport the corresponding commit to fix the clippy
issues.

See: commit 5e52729453

Signed-off-by: Bo Chen <chen.bo@intel.com>

net_util/src/mac.rs

@@ -125,7 +125,7 @@ impl<'de> Deserialize<'de> for MacAddr {
     {
         let s = String::deserialize(deserializer)?;
         MacAddr::parse_str(&s)
-            .map_err(|e| D::Error::custom(format!("The provided MAC address is invalid: {}", e)))
+            .map_err(|e| D::Error::custom(format!("The provided MAC address is invalid: {e}")))
     }
 }
 
@@ -161,7 +161,7 @@ mod tests {
 
         let mac = MacAddr::parse_str("12:34:56:78:9a:BC").unwrap();
 
-        println!("parsed MAC address: {}", mac);
+        println!("parsed MAC address: {mac}");
 
         let bytes = mac.get_bytes();
         assert_eq!(bytes, [0x12u8, 0x34, 0x56, 0x78, 0x9a, 0xbc]);

net_util/src/open_tap.rs

@@ -41,7 +41,7 @@ type Result<T> = std::result::Result<T, Error>;
 fn check_mq_support(if_name: &Option<&str>, queue_pairs: usize) -> Result<()> {
     if let Some(tap_name) = if_name {
         let mq = queue_pairs > 1;
-        let path = format!("/sys/class/net/{}/tun_flags", tap_name);
+        let path = format!("/sys/class/net/{tap_name}/tun_flags");
         // interface does not exist, check is not required
         if !Path::new(&path).exists() {
             return Ok(());

net_util/src/tap.rs

@@ -586,7 +586,7 @@ mod tests {
         let _tap_ip_guard = TAP_IP_LOCK.lock().unwrap();
 
         let t = Tap::new(1).unwrap();
-        println!("created tap: {:?}", t);
+        println!("created tap: {t:?}");
     }
 
     #[test]