scsi: ufs: update UFS initialization sequence

During UFS host init, we calibrate the UFS host PHY with its settings of
HS-Gear3 Rate-B by default. After UFS device is initialized but before
switched to HS mode, if it supports HS-Gear4, do full reset and re-init
the UFS host PHY with its HS-Gear4 Rate-A settings, then start over the UFS
device initialization again.

Change-Id: I8ae1367a97712ba2036c6078e6569df1ed91514d
Signed-off-by: Can Guo <cang@codeaurora.org>