doc: fix events typo

This commit removes an extraneous word.

PR-URL: https://github.com/nodejs/node/pull/7329
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Brian White <mscdex@mscdex.net>

doc/api/events.md

@@ -497,7 +497,7 @@ added for a particular event. This is a useful default that helps finding
 memory leaks. Obviously, not all events should be limited to just 10 listeners.
 The `emitter.setMaxListeners()` method allows the limit to be modified for this
 specific `EventEmitter` instance. The value can be set to `Infinity` (or `0`)
-for to indicate an unlimited number of listeners.
+to indicate an unlimited number of listeners.
 
 Returns a reference to the `EventEmitter` so calls can be chained.