Add a Xilinx CSU DMA module to ZynqMP SoC, and connent the stream
link of GQSPI to CSU DMA.

Signed-off-by: Xuzhou Cheng <xuzhou.cheng@windriver.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20210303135254.3970-4-bmeng.cn@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>