FROMGIT: scsi: ufs: Stop hardcoding the scale down gear

Instead of hardcoding the scale down gear, make it a member of
the ufs_clk_scaling struct.

Link: https://lore.kernel.org/r/1606442334-22641-1-git-send-email-cang@codeaurora.org


Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Bug: 189417930
(cherry picked from commit 29b87e92
git://git.kernel.org/pub/scm/linux/kernel/git/mkp/scsi.git

 5.14/scsi-queue)
Change-Id: I59c0dab392e25b900451284e424b6df82ed69b3a
Signed-off-by: Can Guo <cang@codeaurora.org>