davinci: omapl138_lcdk: add NAND SPL boot support

NAND SPL boot was missing. Add it. The README specific to omapl138-lcdk
is also removed because its content does not apply anymore, i.e. the
generated AIS image can be flashed directly to the NAND without
using any external tool to create and bootable AIS image.

Signed-off-by: Fabien Parent <fparent@baylibre.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/omapl138_lcdk_defconfig b/configs/omapl138_lcdk_defconfig
index 4a5f435..52681c9 100644
--- a/configs/omapl138_lcdk_defconfig
+++ b/configs/omapl138_lcdk_defconfig
@@ -3,6 +3,7 @@
 CONFIG_TARGET_OMAPL138_LCDK=y
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
+CONFIG_SPL_NAND_SUPPORT=y
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_BOOTDELAY=3
 CONFIG_VERSION_VARIABLE=y
@@ -23,6 +24,8 @@
 CONFIG_CMD_EXT2=y
 CONFIG_CMD_FAT=y
 CONFIG_CMD_UBI=y
+CONFIG_SYS_NAND_U_BOOT_LOCATIONS=y
+CONFIG_SYS_NAND_U_BOOT_OFFS=0x28000
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_SPI_FLASH_WINBOND=y