net: hns3: remove hns3_fill_desc_tso

This patch removes hns3_fill_desc_tso in preparation for
fixing some desc filling bug, because for tso or non-tso
case, we will use the unified hns3_fill_desc.

Signed-off-by: Fuyun Liang <liangfuyun1@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>