scsi: hisi_sas: fix the issue of setting linkrate register
It is not right to set the register PROG_PHY_LINK_RATE while PHY is still
enabled. So if we want to change PHY linkrate, we need to disable PHY before
setting the register PROG_PHY_LINK_RATE, and then start-up PHY. This patch
is to fix this issue.
Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>