Restructure and add a defconfig for BeagleBone Black

...which builds upon work by Pieter Smith that was imported in the
previous commit.

Change-Id: I9e83096c45cd83b0bc4e687a64075369b70d0661
diff --git a/configs/czechlight_beaglebone_defconfig b/configs/czechlight_beaglebone_defconfig
new file mode 100644
index 0000000..566dc95
--- /dev/null
+++ b/configs/czechlight_beaglebone_defconfig
@@ -0,0 +1,37 @@
+BR2_arm=y
+BR2_cortex_a8=y
+BR2_ARM_FPU_VFPV3=y
+BR2_KERNEL_MIRROR="http://ftp.fi.muni.cz/pub/linux/kernel/"
+BR2_GNU_MIRROR="http://ftp.fi.muni.cz/pub/gnu/"
+BR2_CPAN_MIRROR="http://ftp.fi.muni.cz/pub/CPAN/"
+BR2_TOOLCHAIN_EXTERNAL=y
+BR2_TARGET_GENERIC_PASSWD_SHA256=y
+BR2_INIT_SYSTEMD=y
+BR2_TARGET_GENERIC_GETTY_PORT="ttyO0"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="$(BR2_EXTERNAL_CZECHLIGHT_PATH)/board/czechlight/beaglebone/post-image.sh"
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.9.18"
+BR2_LINUX_KERNEL_DEFCONFIG="omap2plus"
+BR2_PACKAGE_OPENSSH=y
+BR2_PACKAGE_BASH=y
+BR2_PACKAGE_SYSTEMD_LOGIND=y
+BR2_PACKAGE_UTIL_LINUX_AGETTY=y
+BR2_PACKAGE_VIM=y
+# BR2_PACKAGE_VIM_RUNTIME is not set
+BR2_TARGET_ROOTFS_EXT2=y
+BR2_TARGET_ROOTFS_EXT2_4=y
+BR2_TARGET_BAREBOX=y
+BR2_TARGET_BAREBOX_BOARD_DEFCONFIG="am335x"
+BR2_TARGET_BAREBOX_IMAGE_FILE="images/barebox-am33xx-beaglebone.img"
+BR2_TARGET_BAREBOX_BAREBOXENV=y
+BR2_TARGET_BAREBOX_CUSTOM_ENV=y
+BR2_TARGET_BAREBOX_CUSTOM_ENV_PATH="$(BR2_EXTERNAL_CZECHLIGHT_PATH)/board/czechlight/beaglebone/barebox.env"
+BR2_TARGET_BAREBOX_AUX=y
+BR2_TARGET_BAREBOX_AUX_BOARD_DEFCONFIG="am335x_mlo"
+BR2_TARGET_BAREBOX_AUX_IMAGE_FILE="images/barebox-am33xx-beaglebone-mlo.img"
+BR2_PACKAGE_HOST_DOSFSTOOLS=y
+BR2_PACKAGE_HOST_DTC=y
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_PACKAGE_HOST_MTOOLS=y
+CZECHLIGHT_NETCONF=y