Require two factor authentication for the ACP login only not working

[Greeniously]

Bug in paul999\tfa\helper\session_helper.php

Missing code in public function is_tfa_required, between MODE_REQUIRED_FOR_ACP_LOGIN and MODE_REQUIRED_FOR_ADMIN, is basically making those settings identical.

return ($admin); should work?

Suggested solution:

	public function is_tfa_required($user_id, $admin = false, $userdata = array())
	{
		if (sizeof($this->get_modules()) == 0)
		{
			return false;
		}
		switch ($this->config['tfa_mode'])
		{
			case session_helper_interface::MODE_DISABLED:
				return false;

			case session_helper_interface::MODE_NOT_REQUIRED:
				return $this->is_tfa_registered($user_id);

			case session_helper_interface::MODE_REQUIRED_FOR_ACP_LOGIN:
				return ($admin);
				
			case session_helper_interface::MODE_REQUIRED_FOR_ADMIN:
				return $this->do_permission_check($user_id, $userdata, 'a_');

			case session_helper_interface::MODE_REQUIRED_FOR_MODERATOR:
				return $this->do_permission_check($user_id, $userdata, array('m_', 'a_'));

			case session_helper_interface::MODE_REQUIRED:
				return true;

			default:
				return false;
		}