Uptade targets in case hostname was directly passed without the roster.
        :return:

def _update_targets(self):
        '''
        Uptade targets in case hostname was directly passed without the roster.
        :return:
        '''

        hostname = self.opts.get('tgt', '')
        if '@' in hostname:
            user, hostname = hostname.split('@', 1)
        else:
            user = self.opts.get('ssh_user')
        if hostname == '*':
            hostname = ''

        if salt.utils.network.is_reachable_host(hostname):
            hostname = salt.utils.network.ip_to_host(hostname)
            self.opts['tgt'] = hostname
            self.targets[hostname] = {
                'passwd': self.opts.get('ssh_passwd', ''),
                'host': hostname,
                'user': user,
            }
            if self.opts.get('ssh_update_roster'):
                self._update_roster()