This patch adds the binding documentation for Spreadtrum SPI
controller device.
Signed-off-by: Lanqing Liu <lanqing.liu@spreadtrum.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>