net: hns3: remove the rss_size limitation by vector num

Currently, if user hasn't change channel number, the rss_size
is limited to be no more than the vector number, in order to
keep one vector only being mapped to one queue. But the queue
number of each tc can be different, and one vector also can
be mapped by multiple queues. So remove this limitation.

Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>