net: hns3: optimization for CMDQ uninitialization

When uninitializing CMDQ, HCLGE_STATE_CMD_DISABLE will
be set up firstly, then the driver does not send command
anymore. So, hclge_free_cmd_desc can be called without
holding ring->lock. hclge_destroy_cmd_queue() and
hclge_destroy_queue() are unnecessary now, so removes them,
the VF driver has implemented currently.

BTW, the VF driver should set up HCLGEVF_STATE_CMD_DISABLE
as well in the hclgevf_cmd_uninit(), just likes what the PF
driver does.

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