configs: phycore_am64x_a53_defconfig: Enable ENV_IS_IN_SPI_FLASH

Enable ENV_IS_IN_SPI_FLASH to read the environment from the SPI
flash when booting from it. The oftree, kernel and ramdisk sizes
are located in this environment and therefore required to boot
an initramfs.

Signed-off-by: Daniel Schultz <d.schultz@phytec.de>
Reviewed-by: Wadim Egorov <w.egorov@phytec.de>
diff --git a/configs/phycore_am64x_a53_defconfig b/configs/phycore_am64x_a53_defconfig
index f0c7ee2..4ee1bd8 100644
--- a/configs/phycore_am64x_a53_defconfig
+++ b/configs/phycore_am64x_a53_defconfig
@@ -14,6 +14,7 @@
 CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x80480000
 CONFIG_ENV_SIZE=0x20000
 CONFIG_ENV_OFFSET=0x680000
+CONFIG_ENV_SECT_SIZE=0x20000
 CONFIG_DM_GPIO=y
 CONFIG_SPL_DM_SPI=y
 CONFIG_DEFAULT_DEVICE_TREE="ti/k3-am642-phyboard-electra-rdk"
@@ -91,6 +92,7 @@
 CONFIG_ENV_OVERWRITE=y
 CONFIG_ENV_IS_NOWHERE=y
 CONFIG_ENV_IS_IN_MMC=y
+CONFIG_ENV_IS_IN_SPI_FLASH=y
 CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
 CONFIG_SYS_MMC_ENV_DEV=1
 CONFIG_NET_RANDOM_ETHADDR=y