ARM: AM437x: Sync defconfig between GP and HS EVM

Adds missing NAND option to CONFIG_SYS_EXTRA_OPTIONS for
AM437x HS EVMs. This syncs up the config options between
GP and HS EVMs.

Signed-off-by: Madan Srinivas <madans@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/configs/am437x_hs_evm_defconfig b/configs/am437x_hs_evm_defconfig
index 3cd39eb..e82085b 100644
--- a/configs/am437x_hs_evm_defconfig
+++ b/configs/am437x_hs_evm_defconfig
@@ -10,7 +10,7 @@
 CONFIG_SPL=y
 CONFIG_ISW_ENTRY_ADDR=0x40302ae0
 CONFIG_SPL_STACK_R=y
-CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=1"
+CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=1, NAND"
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_BOOTZ=y
 # CONFIG_CMD_IMLS is not set