Bump buildroot to 2019.02

bsp/buildroot/configs/riotboard_defconfig

@@ -0,0 +1,42 @@
+# architecture
+BR2_arm=y
+BR2_cortex_a9=y
+BR2_ARM_ENABLE_NEON=y
+BR2_ARM_ENABLE_VFP=y
+BR2_ARM_FPU_VFPV3=y
+
+# system
+BR2_TARGET_GENERIC_GETTY=y
+BR2_TARGET_GENERIC_GETTY_PORT="ttymxc1"
+
+# bootloader
+BR2_TARGET_UBOOT=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2018.07"
+BR2_TARGET_UBOOT_BOARDNAME="riotboard"
+BR2_TARGET_UBOOT_FORMAT_IMX=y
+
+# Linux headers same as kernel, a 4.18 series
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_18=y
+
+# kernel
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.18.10"
+BR2_LINUX_KERNEL_DEFCONFIG="imx_v6_v7"
+BR2_LINUX_KERNEL_DTS_SUPPORT=y
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="imx6dl-riotboard"
+BR2_LINUX_KERNEL_INSTALL_TARGET=y
+BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
+
+# required tools to create the SD card image
+BR2_PACKAGE_HOST_DOSFSTOOLS=y
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_PACKAGE_HOST_MTOOLS=y
+
+# rootfs
+BR2_TARGET_ROOTFS_EXT2=y
+BR2_TARGET_ROOTFS_EXT2_4=y
+BR2_ROOTFS_OVERLAY="board/embest/riotboard/rootfs_overlay"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/embest/riotboard/genimage.cfg"