scsi: hisi_sas: use an general way to delay PHY work

scsi: hisi_sas: use an general way to delay PHY work

BugLink: http://bugs.launchpad.net/bugs/1756094
Use an general way to do delay work for a PHY. Then it will be easier to add
new delayed work for a PHY in future.

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>
(cherry picked from commit e537b62b0796042e1ab66657c4dab662d19e9f0b)
Signed-off-by: Manoj Iyer <manoj.iyer@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>