net: hns3: Fix for loopback selftest failed problem

Tqp and mac need to be enabled when doing loopback selftest,
ae_algo->ops->start/stop is used to do the job, there is a
time window between ae_algo->ops->start/stop and loopback setup,
which will cause selftest failed problem when there is frame
coming in during that time window.

This patch fixes it by enabling the tqp and mac during loopback
setup process.

Fixes: c39c4d98 ("net: hns3: Add mac loopback selftest support in hns3 driver")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>