title: Function mcrypt_get_iv_size() is deprecated on Laravel 5.5 and php 7.1.11
body: <p>I have upgraded laravel 5.3 to laravel 5.5 and I am using php 7.1.11</p>
  
  <p>On upgrading I am getting error</p>
  
  <p><code>ErrorException (E_ERROR) Function mcrypt_get_iv_size() is deprecated</code></p>
  
  <p>In <code>config\app</code> I have</p>
  
  <pre><code>'cipher' =&gt; 'AES-256-CBC'
  </code></pre>
  
  <p>Also try adding</p>
  
  <pre><code>error_reporting(E_ALL ^ E_DEPRECATED);
  </code></pre>
  
  <p>to it but still getting error.</p>
  
  <pre><code>$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
  $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
  $crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, self::$skey, $text, MCRYPT_MODE_ECB, $iv);
  </code></pre>
  
  <p>This is code where I am using it.</p>