update icon stateless component

components/icon/index.jsx

@@ -1,9 +1,7 @@
 import React from 'react';
 
-function Icon(props) {
+export default props => {
   let { type, className = '', ...other } = props;
   className += ` anticon anticon-${type}`;
   return <i className={className} {...other} />;
-}
-
-export default Icon;
+};