dts: P1020RDB: Add ESPI slave device node

Add ESPI slave node for P1020RDB.

Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/arch/powerpc/dts/p1020rdb-pc.dts b/arch/powerpc/dts/p1020rdb-pc.dts
index 7ebaa61..4193af1 100644
--- a/arch/powerpc/dts/p1020rdb-pc.dts
+++ b/arch/powerpc/dts/p1020rdb-pc.dts
@@ -30,6 +30,21 @@
 		ranges = <0x01000000 0x0 0x00000000 0x0 0xffc00000 0x0 0x00010000   /* downstream I/O */
 			  0x02000000 0x0 0x80000000 0x0 0x80000000 0x0 0x20000000>; /* non-prefetchable memory */
 	};
+
+	aliases {
+		spi0 = &espi0;
+	};
 };
 
 /include/ "p1020-post.dtsi"
+
+&espi0 {
+	status = "okay";
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		reg = <0>;
+		spi-max-frequency = <10000000>; /* input clock */
+	};
+};