arm: ls1021aqds: Enable driver model lpuart serial driver

Convert ls1021aqds_nor_lpuart and ls1021aqds_ddr4_nor_lpuart
to driver model suport. Enable lpuart port driver.

Signed-off-by: York Sun <york.sun@nxp.com>
CC: Alison Wang <alison.wang@nxp.com>
CC: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alison Wang <alison.wang@nxp.com>

arch/arm/dts/Makefile

@@ -97,6 +97,7 @@ dtb-$(CONFIG_TARGET_BEAGLE_X15) += am57xx-beagle-x15.dtb
 dtb-$(CONFIG_TARGET_STV0991) += stv0991.dtb
 
 dtb-$(CONFIG_LS102XA) += ls1021a-qds-duart.dtb \
+	ls1021a-qds-lpuart.dtb \
 	ls1021a-twr-duart.dtb ls1021a-twr-lpuart.dtb
 dtb-$(CONFIG_FSL_LSCH3) += fsl-ls2080a-qds.dtb \
 	fsl-ls2080a-rdb.dtb

arch/arm/dts/ls1021a-qds-lpuart.dts

@@ -0,0 +1,16 @@
+/*
+ * Freescale ls1021a QDS board common device tree source
+ *
+ * Copyright 2013-2015 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/dts-v1/;
+#include "ls1021a-qds.dtsi"
+
+/ {
+	chosen {
+		stdout-path = &lpuart0;
+	};
+};

configs/ls1021aqds_ddr4_nor_lpuart_defconfig

@@ -1,7 +1,11 @@
 CONFIG_ARM=y
 CONFIG_TARGET_LS1021AQDS=y
 CONFIG_SYS_EXTRA_OPTIONS="SYS_FSL_DDR4,LPUART"
+CONFIG_DM_SERIAL=y
+CONFIG_DEFAULT_DEVICE_TREE="ls1021a-qds-lpuart"
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_OF_CONTROL=y
+CONFIG_DM=y
 CONFIG_NETDEVICES=y
 CONFIG_E1000=y
 CONFIG_FSL_LPUART=y

configs/ls1021aqds_nor_lpuart_defconfig

@@ -1,7 +1,11 @@
 CONFIG_ARM=y
 CONFIG_TARGET_LS1021AQDS=y
+CONFIG_DM_SERIAL=y
+CONFIG_DEFAULT_DEVICE_TREE="ls1021a-qds-lpuart"
 CONFIG_SYS_EXTRA_OPTIONS="LPUART"
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_OF_CONTROL=y
+CONFIG_DM=y
 CONFIG_NETDEVICES=y
 CONFIG_E1000=y
 CONFIG_FSL_LPUART=y