net: hns3: remove an unnecessary check in hclge_set_umv_space()

mainline inclusion
from mainline-v5.8-rc1
commit 3fd8dc26
category: cleanup
bugzilla: NA
CVE: NA

----------------------------

Since hclge_set_umv_space() is only called by hclge_init_umv_space(),
parameter 'allocated_size' will not be NULL.

Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Reviewed-by: li yongxin <liyongxin1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>