Add spidev to 500 dts for test image

recipes-kernel/linux/linux-fslc-imx/device-tree/vesta-500.dts

@@ -485,6 +485,20 @@
 		status = "okay";
 };
 
+&ecspi1 {
+        pinctrl-names = "default";
+        pinctrl-0 = <&pinctrl_ecspi1>;
+        fsl,spi-num-chipselects = <1>;
+        cs-gpios = <&gpio3 26 GPIO_ACTIVE_LOW>;
+        status = "okay";
+
+        spidev0: spi@0 {
+                compatible = "spidev";
+                reg = <0>;
+                spi-max-frequency = <8000000>;
+        };
+};
+
 /* Vesta expansion card DT overlay manager - based on beaglebone cape manager */
 
 / {