udoo: Switch to SPL support

Currently we need to build one U-boot image for each of the udoo
variants: quad and dual-lite.

By switching to SPL we can support all two variants with a single binary.

Based on the SPL for wandboard.

Tested with OpenELEC (Open Embedded Linux Entertainment Center)
on both boards.

Signed-off-by: Peter Vicman <peter.vicman@gmail.com>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
Acked-by: Stefano Babic <sbabic@denx.de>
Signed-off-by: Peter Vicman <peter.vicman@gmail.com>
Acked-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/configs/udoo_defconfig b/configs/udoo_defconfig
new file mode 100644
index 0000000..9fe30d3
--- /dev/null
+++ b/configs/udoo_defconfig
@@ -0,0 +1,6 @@
+CONFIG_SPL=y
+CONFIG_ARM=y
+CONFIG_DM=y
+CONFIG_DM_THERMAL=y
+CONFIG_TARGET_UDOO=y
+CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/imx-common/spl_sd.cfg,MX6QDL"