armv7: ls1021aiot: Fixing SPL compiling issues

To align with SPL change 38fed8ab and 693d4c9f, add Kconfig option
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR to defconfig, and remove
CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS.

Signed-off-by: York Sun <york.sun@nxp.com>
CC: Feng Li <feng.li_2@nxp.com>
diff --git a/configs/ls1021aiot_sdcard_defconfig b/configs/ls1021aiot_sdcard_defconfig
index 4b082ab..a5a391d 100644
--- a/configs/ls1021aiot_sdcard_defconfig
+++ b/configs/ls1021aiot_sdcard_defconfig
@@ -1,6 +1,8 @@
 CONFIG_ARM=y
 CONFIG_TARGET_LS1021AIOT=y
 CONFIG_SPL=y
+CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR=y
+CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0xe8
 CONFIG_DEFAULT_DEVICE_TREE="ls1021a-iot-duart"
 CONFIG_DM_SPI=y
 CONFIG_SYS_EXTRA_OPTIONS="RAMBOOT_PBL,SPL_FSL_PBL,SD_BOOT,SD_BOOT_QSPI"