net: hns3: add cmdq check for vf periodic service task

When the vf cmdq is disabled, there is no need to keep these task running.
So this patch skip these task when the cmdq is disabled.

Fixes: ff200099 ("net: hns3: remove unnecessary work in hclgevf_main")
Signed-off-by: Jie Wang <wangjie125@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>