dts: imx6ul_evk: Add DTS files for 14x14 EVK and 9x9 EVK boards

Add the board DTS files for 14x14 EVK and 9x9 EVK. They are necessary
for converting to use u-boot DM driver.

Two -u-boot.dtsi are added to modify compatible string of SPI flash
device to "spi-flash".

Signed-off-by: Ye Li <ye.li@nxp.com>
diff --git a/arch/arm/dts/imx6ul-9x9-evk-u-boot.dtsi b/arch/arm/dts/imx6ul-9x9-evk-u-boot.dtsi
new file mode 100644
index 0000000..db640d6
--- /dev/null
+++ b/arch/arm/dts/imx6ul-9x9-evk-u-boot.dtsi
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018 NXP
+ */
+
+&qspi {
+	flash0: n25q256a@0 {
+		compatible = "spi-flash";
+	};
+};
\ No newline at end of file