spi: dt-bindings: mtk-snfi: Add read latch latency property

Add mediatek,rx-latch-latency-ns property which adjust data read
latch latency in the unit of nanoseconds.
Signed-off-by: Xiangsheng Hou <xiangsheng.hou@mediatek.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230201020921.26712-6-xiangsheng.hou@mediatek.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml

@@ -45,6 +45,9 @@ properties:
     description: device-tree node of the accompanying ECC engine.
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  mediatek,rx-latch-latency-ns:
+    description: Data read latch latency, unit is nanoseconds.
+
 required:
   - compatible
   - reg