Fix typo - Remove duplicated "to have"

Summary: Closes https://github.com/facebook/react-native/pull/3015

Reviewed By: @​svcscm

Differential Revision: D2530576

Pulled By: @vjeux

fb-gh-sync-id: e7df3706f3c733e8de32c1f123d951b488133e8a

Libraries/Components/Touchable/TouchableHighlight.js

@@ -59,7 +59,7 @@ var DEFAULT_PROPS = {
  * ```
  * > **NOTE**: TouchableHighlight supports only one child
  * >
- * > If you wish to have to have several child components, wrap them in a View.
+ * > If you wish to have several child components, wrap them in a View.
  */
 
 var TouchableHighlight = React.createClass({