Typo in the name of variable

Author: javorszky

src/nodejs/unit-http/http.js

@@ -14,7 +14,7 @@ const {
 
 function createServer (options, requestHandler) {
     if (typeof options === 'function') {
-        requestListener = options;
+        requestHandler = options;
         options = {};
     } else {
         stderr.write('createServer was called with an options object. Unit ignores this for the time being.');