boards: spresense: Add elf configuration

NOTE: you need to apply another PR to apps to avoid crash in task test

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

boards/arm/cxd56xx/spresense/configs/elf/defconfig

@@ -0,0 +1,57 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_CXD56_I2C0_SCUSEQ is not set
+# CONFIG_STANDARD_SERIAL is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="spresense"
+CONFIG_ARCH_BOARD_SPRESENSE=y
+CONFIG_ARCH_CHIP="cxd56xx"
+CONFIG_ARCH_CHIP_CXD56XX=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARMV7M_USEBASEPRI=y
+CONFIG_BOARD_LOOPSPERMSEC=5434
+CONFIG_BOOT_RUNFROMISRAM=y
+CONFIG_BUILTIN=y
+CONFIG_CLOCK_MONOTONIC=y
+CONFIG_CXD56_BINARY=y
+CONFIG_CXD56_I2C0=y
+CONFIG_CXD56_I2C=y
+CONFIG_CXD56_SPI4=y
+CONFIG_CXD56_SPI5=y
+CONFIG_CXD56_SPI=y
+CONFIG_ELF=y
+CONFIG_EXAMPLES_ELF=y
+CONFIG_FS_PROCFS=y
+CONFIG_FS_PROCFS_REGISTER=y
+CONFIG_FS_ROMFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_I2C=y
+CONFIG_LIB_BOARDCTL=y
+CONFIG_LIB_ENVPATH=y
+CONFIG_MAX_TASKS=16
+CONFIG_MAX_WDOGPARMS=2
+CONFIG_NFILE_DESCRIPTORS=8
+CONFIG_NFILE_STREAMS=8
+CONFIG_PATH_INITIAL="/mnt/romfs"
+CONFIG_PREALLOC_MQ_MSGS=4
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_PREALLOC_WDOGS=16
+CONFIG_RAM_SIZE=1572864
+CONFIG_RAM_START=0x0d000000
+CONFIG_RR_INTERVAL=200
+CONFIG_RTC=y
+CONFIG_RTC_DRIVER=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_SDCLONE_DISABLE=y
+CONFIG_SPI=y
+CONFIG_START_DAY=4
+CONFIG_START_MONTH=2
+CONFIG_START_YEAR=2020
+CONFIG_SYMTAB_ORDEREDBYNAME=y
+CONFIG_UART1_SERIAL_CONSOLE=y
+CONFIG_USER_ENTRYPOINT="elf_main"