Cadence SD/SDIO/eMMC Host Controller (SD4HC) is an SDHCI compatible
controller. The SDHCI compatible registers start from offset 0x200,
which are called Slot Register Set (SRS) in its datasheet.

This creates a Cadence SDHCI model built on top of the existing
generic SDHCI model. Cadence specific Host Register Set (HRS) is
implemented to make guest software happy.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <1598924352-89526-8-git-send-email-bmeng.cn@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>