Attach power off hook to Cadence UFS driver.

Link: https://lore.kernel.org/r/1576491432-631-1-git-send-email-sheebab@cadence.comReviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Sheeba B <sheebab@cadence.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>