hw/misc: Introduce the Xilinx CFI interface

Introduce the Xilinx Configuration Frame Interface (CFI) for transmitting
CFI data packets between the Xilinx Configuration Frame Unit models
(CFU_APB, CFU_FDRO and CFU_SFR), the Xilinx CFRAME controller (CFRAME_REG)
and the Xilinx CFRAME broadcast controller (CFRAME_BCAST_REG) models (when
emulating bitstream programming and readback).

Signed-off-by: Francisco Iglesias <francisco.iglesias@amd.com>
Reviewed-by: Sai Pavan Boddu <sai.pavan.boddu@amd.com>
Acked-by: Edgar E. Iglesias <edgar@zeroasic.com>
Message-id: 20230831165701.2016397-2-francisco.iglesias@amd.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>