imx: mx6ull/z_14x14_evk: clean up UART iomux
After DM_SERIAL, and set pinctrl_uart1 as pre-reloc, no need initialize
iomux at board file.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/dts/imx6ull-14x14-evk-u-boot.dtsi b/arch/arm/dts/imx6ull-14x14-evk-u-boot.dtsi
new file mode 100644
index 0000000..d283e815
--- /dev/null
+++ b/arch/arm/dts/imx6ull-14x14-evk-u-boot.dtsi
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2022 NXP
+ */
+
+&pinctrl_uart1 {
+ u-boot,dm-pre-reloc;
+};