scsi: ufs: Add driver for TI wrapper for Cadence UFS IP

TI's J721e SoC has a Cadence UFS IP with a TI specific wrapper. This is a
minimal driver to configure the wrapper. It releases the UFS slave device
out of reset and sets up registers to indicate PHY reference clock input
frequency before probing child Cadence UFS driver.

Link: https://lore.kernel.org/r/20191108164857.11466-3-vigneshr@ti.com


Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>