Fix new clippy warnings

src/virtual_device.rs

@@ -119,8 +119,7 @@ impl smoltcp::phy::TxToken for TxToken {
     where
         F: FnOnce(&mut [u8]) -> smoltcp::Result<R>,
     {
-        let mut buffer = Vec::new();
+        let mut buffer = vec![0; len];
-        buffer.resize(len, 0);
         let result = f(&mut buffer);
         self.sender
             .send(Event::OutboundInternetPacket(buffer.into()));

src/virtual_iface/tcp.rs

@@ -229,7 +229,7 @@ impl VirtualInterfacePoll for TcpVirtualInterface {
                                 next_poll = None;
                             }
                         }
-                        Event::VirtualDeviceFed(protocol) if protocol == PortProtocol::Tcp => {
+                        Event::VirtualDeviceFed(PortProtocol::Tcp) => {
                             next_poll = None;
                         }
                         _ => {}

src/virtual_iface/udp.rs

@@ -198,7 +198,7 @@ impl VirtualInterfacePoll for UdpVirtualInterface {
                             }
                             next_poll = None;
                         }
-                        Event::VirtualDeviceFed(protocol) if protocol == PortProtocol::Udp => {
+                        Event::VirtualDeviceFed(PortProtocol::Udp) => {
                             next_poll = None;
                         }
                         _ => {}