'Get link show output for VFs
get vf link show command output filtered by given vf list
@param vf_list: list of vf indexes
@param link_show_out: link show command output
@return: list of output rows regarding given vf_list'

def _get_vf_link_show(self, vf_list, link_show_out):

    vf_lines = []
    for line in link_show_out.split('\n'):
        line = line.strip()
        if line.startswith('vf'):
            details = line.split()
            index = int(details[1])
            if (index in vf_list):
                vf_lines.append(line)
    if (not vf_lines):
        LOG.warning(_LW('Cannot    find    vfs    %(vfs)s    in    device    %(dev_name)s'), {'vfs': vf_list, 'dev_name': self.dev_name})
    return vf_lines
