configs: Migrate CMD_NAND*

Migrate all remaining instances of CMD_NAND, CMD_NAND_TRIMFFS
CMD_NAND_LOCK_UNLOCK and CMD_NAND_TORTURE from the headers into the
defconfig files.

Tested-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/configs/km_kirkwood_128m16_defconfig b/configs/km_kirkwood_128m16_defconfig
index e3b52b0..bbc43c0 100644
--- a/configs/km_kirkwood_128m16_defconfig
+++ b/configs/km_kirkwood_128m16_defconfig
@@ -15,6 +15,7 @@
 CONFIG_CMD_GREPENV=y
 CONFIG_CMD_EEPROM=y
 # CONFIG_CMD_FLASH is not set
+CONFIG_CMD_NAND=y
 CONFIG_CMD_SF=y
 CONFIG_CMD_I2C=y
 CONFIG_CMD_DHCP=y