avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/arch/nds32/cpu/n1213/ag101/Makefile

@@ -0,0 +1,21 @@
+#
+# (C) Copyright 2009
+# Marvell Semiconductor <www.marvell.com>
+# Written-by: Prafulla Wadaskar <prafulla@marvell.com>
+#
+# Copyright (C) 2011 Andes Technology Corporation
+# Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com>
+# Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y	:= cpu.o timer.o
+
+ifndef CONFIG_SKIP_LOWLEVEL_INIT
+obj-y	+= lowlevel_init.o
+endif
+
+ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG
+obj-y	+= watchdog.o
+endif