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/board/xilinx/zynq/xil_io.h

@@ -0,0 +1,13 @@
+/*
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#ifndef XIL_IO_H           /* prevent circular inclusions */
+#define XIL_IO_H
+
+/*
+ * This empty file is here because ps7_init_gpl.c exported by hw project
+ * has #include "xil_io.h" line.
+ */
+
+#endif /* XIL_IO_H */