FROMLIST: scsi: ufs: Add dev ref clock gating wait time support

In UFS version 3.0, a newly added attribute bRefClkGatingWaitTime defines
the minimum time for which the reference clock is required by device during
transition to LS-MODE or HIBERN8 state. Make this change to reflect the new
requirement by adding delays before turning off the clock.

Bug: 143632303
Change-Id: I8d5c1dfcb8cdf0e829933d34a7e9bb207d0e1084
Link: https://lore.kernel.org/patchwork/patch/1149892/


Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>