fix #28198752

ext4 encryption will increase lock contention when opening directory and
result in performance drop in case will-it-scale open1.
Since we don't have explicit usecases as of now, so we decide to disabed
it.
Signed-off-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: NDust Li <dust.li@linux.alibaba.com>