scsi: ufs-msm: switch off PHY PLL power rail during hibern8

If UniPro link is in Hibern8 state, low noise analog power rail for PLL
can be switched off along with main PHY analog power.

Change-Id: I20b113e5f004c824c330f72dc7649dac961bfe3e
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>