net: hns3: create common cmdq init and uninit APIs

The PF and VF cmdq init and uninit APIs are also almost same espect the
suffixes of API names.

This patch creates common cmdq init and uninit APIs needed by PF and VF
cmdq modules. The next patch will use the new unified APIs to replace init
and uninit APIs in PF module.

Signed-off-by: Jie Wang <wangjie125@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>