board: cssi: Migrate to hashed password

Use a hashed password instead of clear text in order to
improve board security.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
diff --git a/configs/MCR3000_defconfig b/configs/MCR3000_defconfig
index fc2bf5b..d113ffe 100644
--- a/configs/MCR3000_defconfig
+++ b/configs/MCR3000_defconfig
@@ -24,8 +24,11 @@
 CONFIG_SYS_MONITOR_BASE=0x04000000
 CONFIG_BOOTDELAY=5
 CONFIG_AUTOBOOT_KEYED=y
+CONFIG_AUTOBOOT_FLUSH_STDIN=y
 CONFIG_AUTOBOOT_PROMPT="\nEnter password - autoboot in %d sec...\n"
-CONFIG_AUTOBOOT_DELAY_STR="root"
+CONFIG_AUTOBOOT_ENCRYPTION=y
+CONFIG_AUTOBOOT_STOP_STR_ENABLE=y
+CONFIG_AUTOBOOT_STOP_STR_SHA256="4813494d137e1631bba301d5acab6e7bb7aa74ce1185d456565ef51d737677b2"
 CONFIG_USE_BOOTCOMMAND=y
 CONFIG_BOOTCOMMAND="run flashboot"
 # CONFIG_HWCONFIG is not set