net: fix debug for dnsopts

Prevent debug call from showing [object Object] for dnsopts in
lookupAndConnect

PR-URL: #2059
Reviewed-by: Colin Ihrig <cjihrig@gmail.com>

lib/net.js

@@ -941,7 +941,7 @@ function lookupAndConnect(self, options) {
     dnsopts.hints = dns.ADDRCONFIG | dns.V4MAPPED;
 
   debug('connect: find host ' + host);
-  debug('connect: dns options ' + dnsopts);
+  debug('connect: dns options', dnsopts);
   self._host = host;
   var lookup = options.lookup || dns.lookup;
   lookup(host, dnsopts, function(err, ip, addressType) {