boards: meson: add g12a u200

The Amlogic U200 board is based on the Amlogic S905D2 SoC
from the Amlogic G12A SoC family.

The board has the following specifications :
 - Amlogic S905D2 ARM Cortex-A53 quad-core SoC
 - XGB DDR4 SDRAM
 - 10/100 Ethernet (Internal PHY)
 - 1 x USB 3.0 Host
 - eMMC
 - SDcard
 - Infrared receiver
 - SDIO WiFi Module
 - MIPI DSI Connector
 - Audio HAT Connector
 - PCI-E M.2 Connector

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/configs/u200_defconfig b/configs/u200_defconfig
new file mode 100644
index 0000000..c351913
--- /dev/null
+++ b/configs/u200_defconfig
@@ -0,0 +1,40 @@
+CONFIG_ARM=y
+CONFIG_ARCH_MESON=y
+CONFIG_SYS_TEXT_BASE=0x01000000
+CONFIG_MESON_G12A=y
+CONFIG_DEBUG_UART_BASE=0xff803000
+CONFIG_DEBUG_UART_CLOCK=24000000
+CONFIG_IDENT_STRING=" u200"
+CONFIG_DEBUG_UART=y
+CONFIG_NR_DRAM_BANKS=1
+CONFIG_OF_BOARD_SETUP=y
+CONFIG_MISC_INIT_R=y
+# CONFIG_DISPLAY_CPUINFO is not set
+CONFIG_DISPLAY_BOARDINFO=y
+# CONFIG_CMD_BDI is not set
+# CONFIG_CMD_IMI is not set
+CONFIG_CMD_GPIO=y
+# CONFIG_CMD_LOADS is not set
+CONFIG_CMD_MMC=y
+# CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_REGULATOR=y
+CONFIG_OF_CONTROL=y
+CONFIG_DEFAULT_DEVICE_TREE="meson-g12a-u200"
+CONFIG_NET_RANDOM_ETHADDR=y
+CONFIG_DM_GPIO=y
+CONFIG_DM_MMC=y
+CONFIG_MMC_MESON_GX=y
+CONFIG_PHY_ADDR_ENABLE=y
+CONFIG_PHY_ADDR=8
+CONFIG_DM_ETH=y
+CONFIG_ETH_DESIGNWARE=y
+CONFIG_PINCTRL=y
+CONFIG_PINCTRL_MESON_G12A=y
+CONFIG_DM_REGULATOR=y
+CONFIG_DM_REGULATOR_FIXED=y
+CONFIG_DM_RESET=y
+CONFIG_DEBUG_UART_MESON=y
+CONFIG_DEBUG_UART_ANNOUNCE=y
+CONFIG_DEBUG_UART_SKIP_INIT=y
+CONFIG_MESON_SERIAL=y
+CONFIG_OF_LIBFDT_OVERLAY=y