net: hns3: remove unnecessary variable initialization

If a variable is assigned a value before it is used, it's no
need to assign an initial value to the variable. So remove
these redundant operations.

Signed-off-by: Yufeng Mo <moyufeng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>