net: fix permanent deopt

PR-URL: https://github.com/nodejs/node/pull/13384
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>

lib/net.js

@@ -949,8 +949,8 @@ Socket.prototype.connect = function() {
     // TODO(joyeecheung): use destructuring when V8 is fast enough
     normalized = normalizeArgs(args);
   }
-  const options = normalized[0];
+  var options = normalized[0];
-  const cb = normalized[1];
+  var cb = normalized[1];
 
   if (this.write !== Socket.prototype.write)
     this.write = Socket.prototype.write;