HW supports a variety of different speed, but the current speed
is fixed.

The real speed should be querried from ethernet.

Fixes: 9a443537 ("IB/hns: Add driver files for hns RoCE driver")
Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Link: https://lore.kernel.org/r/20230804012711.808069-2-huangjunxian6@hisilicon.comSigned-off-by: Leon Romanovsky <leon@kernel.org>