Update user.class.php

Correct a small mistake.

controller/user.class.php

@@ -171,7 +171,7 @@ class user extends Controller
      * 登录数据提交处理
      */
     public function loginSubmit(){
-        if(!isset($this->in['name']) || !isset($this->in['password'])) {
+        if(isset($this->in['name']) || isset($this->in['password'])) {
             $msg = $this->L['login_not_null'];
         }else{
             //错误三次输入验证码            
@@ -289,4 +289,4 @@ class user extends Controller
         $_SESSION['check_code'] = strtolower($code);
         check_code($code);
     }
-}
+}