scsi: ufs: prevent auto-hibern8 trigger during clock frequency scaling

If auto hibern8 is supported then we should manually put the link in
hibern8 before clock frequency scaling sequence to avoid auto hibern8
racing during clock frequency scaling sequence. Othewise, we may
see UFS command or hibern8 issues after the scaling sequence completion.

Change-Id: I6a126029be6fb03ba4b387fbdfa89e068882a54f
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>