net: hns3: fix unsupported config for RSS

driver inclusion
category: bugfix
bugzilla: NA
CVE: NA

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For revision 0x20, rss_tuple_set field does not support in VF,
so this patch fixes this case.

Signed-off-by: Guojia Liao <liaoguojia@huawei.com>
Signed-off-by: shenhao <shenhao21@huawei.com>
Reviewed-by: Zhong Zhaohui <zhongzhaohui@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>