stm32ldiscovery/chrono: add CONFIG_SLCD

This is to unblock CI check,
https://github.com/apache/nuttx/actions/runs/12628628318/job/35185115826

following suggestion per:
apache#15423 (review)

Signed-off-by: Yanfeng Liu <[email protected]>

Author: yf13

boards/arm/stm32/stm32ldiscovery/configs/chrono/defconfig

@@ -50,6 +50,7 @@ CONFIG_RAW_BINARY=y
 CONFIG_RR_INTERVAL=200
 CONFIG_RTC_DATETIME=y
 CONFIG_SCHED_WAITPID=y
+CONFIG_SLCD=y
 CONFIG_STANDARD_SERIAL=y
 CONFIG_START_DAY=19
 CONFIG_START_MONTH=5