修正添加、编辑节点未填写IPv6无法提交问题

app/Http/Controllers/AdminController.php

@@ -418,7 +418,7 @@ class AdminController extends Controller
                 return Response::json(['status' => 'fail', 'data' => '', 'message' => '添加失败：IPv4地址不合法']);
             }
 
-            if (false === filter_var($request->get('ipv6'), FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
+            if ($request->get('ipv6') && false === filter_var($request->get('ipv6'), FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
                 return Response::json(['status' => 'fail', 'data' => '', 'message' => '添加失败：IPv6地址不合法']);
             }
 
@@ -532,7 +532,7 @@ class AdminController extends Controller
                 return Response::json(['status' => 'fail', 'data' => '', 'message' => '添加失败：IPv4地址不合法']);
             }
 
-            if (false === filter_var($ipv6, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
+            if ($request->get('ipv6') && false === filter_var($ipv6, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
                 return Response::json(['status' => 'fail', 'data' => '', 'message' => '添加失败：IPv6地址不合法']);
             }