imx: imx8mn: enable CONFIG_CMD_ERASEENV

enable CONFIG_CMD_ERASEENV to make it easy to erase env.
Use savedefconfig to generate new defconfig.

Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/configs/imx8mn_ddr4_evk_defconfig b/configs/imx8mn_ddr4_evk_defconfig
index 50b03d0..a63177e 100644
--- a/configs/imx8mn_ddr4_evk_defconfig
+++ b/configs/imx8mn_ddr4_evk_defconfig
@@ -7,12 +7,15 @@
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_SYS_MALLOC_F_LEN=0x10000
+CONFIG_SYS_I2C_MXC_I2C1=y
+CONFIG_SYS_I2C_MXC_I2C2=y
+CONFIG_SYS_I2C_MXC_I2C3=y
+CONFIG_ENV_SIZE=0x1000
+CONFIG_ENV_OFFSET=0x400000
 CONFIG_TARGET_IMX8MN_EVK=y
 CONFIG_SPL_MMC_SUPPORT=y
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_SPL_DRIVERS_MISC_SUPPORT=y
-CONFIG_ENV_SIZE=0x1000
-CONFIG_ENV_OFFSET=0x400000
 CONFIG_SPL=y
 CONFIG_SPL_IMX_ROMAPI_LOADADDR=0x48000000
 CONFIG_SPL_TEXT_BASE=0x912000
@@ -32,6 +35,7 @@
 CONFIG_SYS_PROMPT="u-boot=> "
 # CONFIG_CMD_EXPORTENV is not set
 # CONFIG_CMD_IMPORTENV is not set
+CONFIG_CMD_ERASEENV=y
 # CONFIG_CMD_CRC32 is not set
 CONFIG_CMD_CLK=y
 CONFIG_CMD_FUSE=y
@@ -59,9 +63,6 @@
 CONFIG_MXC_GPIO=y
 CONFIG_DM_I2C=y
 CONFIG_SYS_I2C_MXC=y
-CONFIG_SYS_I2C_MXC_I2C1=y
-CONFIG_SYS_I2C_MXC_I2C2=y
-CONFIG_SYS_I2C_MXC_I2C3=y
 CONFIG_DM_MMC=y
 CONFIG_SUPPORT_EMMC_BOOT=y
 CONFIG_FSL_ESDHC_IMX=y