benchmark: fix linting errors

4d78121 had lint errors that went
undetected. This fixes them.

PR-URL: #5840
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

benchmark/http_simple_auto.js

@@ -13,7 +13,7 @@ var spawn = require('child_process').spawn;
 
 var port = parseInt(process.env.PORT || 8000);
 
-var fixed = "C".repeat(20 * 1024);
+var fixed = 'C'.repeat(20 * 1024);
 
 var stored = {};
 var storedBuffer = {};
@@ -26,13 +26,14 @@ var server = http.createServer(function(req, res) {
   var n_chunks = parseInt(commands[3], 10);
   var status = 200;
   var n;
+  var i;
 
   if (command == 'bytes') {
     n = parseInt(arg, 10);
     if (n <= 0)
       throw new Error('bytes called with n <= 0');
     if (stored[n] === undefined) {
-      stored[n] = "C".repeat(n);
+      stored[n] = 'C'.repeat(n);
     }
     body = stored[n];