chore: fix lint errors

* check error
* remove unused function

mitm/mitm.go

@@ -221,7 +221,11 @@ func Serve(ctx context.Context, log *slog.Logger) error {
 			break
 		}
 		// accept incoming connections
-		listener.SetDeadline(time.Now().Add(listenTimeout))
+		if err = listener.SetDeadline(time.Now().Add(listenTimeout)); err != nil {
+			log.Error("couldn't set deadline on listener", slog.Any("error", err))
+			cancel()
+			break
+		}
 		conn, err := listener.Accept()
 		if err != nil {
 			// check if timeout reached

mitm/outbound.go

@@ -193,15 +193,6 @@ func parseTimeSync(cleartext []byte) (*OutboundTimeSync, error) {
 	return &body, nil
 }
 
-// deviceModel takes a device ID and returns the device model if the device is
-// known. If the device is not known it returns an error.
-func deviceModel(deviceID [8]byte) (string, error) {
-	if model, ok := deviceIDToModel[deviceID]; ok {
-		return model, nil
-	}
-	return "", fmt.Errorf("unknown device ID: %v", deviceID)
-}
-
 // handleTimeSyncPacket handles time sync packet envelope and ciphertext.
 func handleTimeSyncPacket(
 	buf *bytes.Buffer,