configs/nitrogen6*: update to use genimage

Also updating the documentation with the dd instruction to flash the
bootable media.

Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

board/boundarydevices/nitrogen6x/genimage.cfg

@@ -0,0 +1,16 @@
+image sdcard.img {
+	hdimage {
+	}
+
+	partition u-boot {
+		in-partition-table = "no"
+		image = "u-boot.imx"
+		offset = 1024
+	}
+
+	partition rootfs {
+		partition-type = 0x83
+		image = "rootfs.ext4"
+		size = 512M
+	}
+}

board/boundarydevices/nitrogen6x/post-image.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+BOARD_DIR="$(dirname $0)"
+GENIMAGE_CFG="${BOARD_DIR}/genimage.cfg"
+GENIMAGE_TMP="${BUILD_DIR}/genimage.tmp"
+
+rm -rf "${GENIMAGE_TMP}"
+
+genimage                           \
+	--rootpath "${TARGET_DIR}"     \
+	--tmppath "${GENIMAGE_TMP}"    \
+	--inputpath "${BINARIES_DIR}"  \
+	--outputpath "${BINARIES_DIR}" \
+	--config "${GENIMAGE_CFG}"
+
+exit $?

board/boundarydevices/nitrogen6x/readme.txt

@@ -2,11 +2,11 @@ Buildroot for Boundary Devices Nitrogen6X:
 
 http://boundarydevices.com/products/nitrogen6x-board-imx6-arm-cortex-a9-sbc/
 
-To install, simply write rootfs.ext2 to the first partition of a uSD card:
+To install, simply copy the image to a uSD card:
 
-sudo dd if=output/images/rootfs.ext2 of=/dev/sdX1
+sudo dd if=output/images/sdcard.img of=/dev/sdX
 
-Where 'sdX1' is the device node of the uSD partition.
+Where 'sdX' is the device node of the uSD partition.
 
 To upgrade u-boot, cancel autoboot and type: