Add Support for UFS Host Controller Interface (UFSHCI) for communicating
with Universal Flash Storage (UFS) devices. The steps to initialize the
host controller interface are the following:

- Initiate the Host Controller Initialization process by writing to the
Host controller enable register.
- Configure the Host Controller base address registers by allocating a
host memory space and related data structures.
- Unipro link startup procedure
- Check for connected device
- Configure UFS host controller to process requests

Also register this host controller as a SCSI host controller.

Taken from Linux Kernel v5.2 (drivers/scsi/ufs/ufshcd.c) and ported to
U-boot.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>