board: amlogic: add support for S400 board

The S400 board is the Amlogic AXG SoC reference board including :
 - Amlogic A113DX ARM Cortex-A53 quad-core SoC @ 1.2GHz
 - 1GB DDR4 SDRAM
 - 10/100 Ethernet
 - 2 x USB 2.0 Host
 - eMMC
 - Infrared receiver
 - SDIO WiFi Module
 - MIPI DSI Connector
 - Audio HAT Connector
 - PCI-E M.2 Connectors

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/board/amlogic/s400/Makefile b/board/amlogic/s400/Makefile
new file mode 100644
index 0000000..bf03862
--- /dev/null
+++ b/board/amlogic/s400/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2016 BayLibre, SAS
+# Author: Neil Armstrong <narmstrong@baylibre.com>
+
+obj-y	:= s400.o