configs: add defconfig for Atmel sama5d3 Xplained

BR2_arm=y

BR2_cortex_a5=y

BR2_ARM_EABIHF=y

BR2_ARM_FPU_VFPV4D16=y

BR2_ARM_INSTRUCTIONS_THUMB2=y

BR2_KERNEL_HEADERS_VERSION=y

BR2_DEFAULT_KERNEL_VERSION="3.18"

BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_3_18=y

BR2_LINUX_KERNEL=y

BR2_LINUX_KERNEL_CUSTOM_GIT=y

BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/linux4sam/linux-at91.git"

BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="03329ca4cf6b94acc5c65b59b2d1f90fdeee0887"

BR2_LINUX_KERNEL_DEFCONFIG="sama5"

BR2_LINUX_KERNEL_ZIMAGE=y

BR2_LINUX_KERNEL_DTS_SUPPORT=y

BR2_LINUX_KERNEL_INTREE_DTS_NAME="at91-sama5d3_xplained at91-sama5d3_xplained_pda4 at91-sama5d3_xplained_pda7"

BR2_TARGET_ROOTFS_UBIFS=y

BR2_TARGET_ROOTFS_UBIFS_LEBSIZE=0x1f000

BR2_TARGET_ROOTFS_UBI=y

BR2_TARGET_ROOTFS_UBI_SUBSIZE=2048

BR2_TARGET_AT91BOOTSTRAP3=y

BR2_TARGET_AT91BOOTSTRAP3_DEFCONFIG="sama5d3_xplainednf_uboot"

BR2_TARGET_UBOOT=y

BR2_TARGET_UBOOT_BOARDNAME="sama5d3_xplained_nandflash"

BR2_TARGET_UBOOT_CUSTOM_GIT=y

BR2_TARGET_UBOOT_CUSTOM_REPO_URL="git://github.com/linux4sam/u-boot-at91.git"

BR2_TARGET_UBOOT_CUSTOM_REPO_VERSION="677f3c2340b72131beebace8e96cac17b9569887"

BR2_TARGET_UBOOT_SPL=y

BR2_PACKAGE_HOST_SAM_BA=y