since we can query this value by MTDIOC_ERASESTATE after:
commit 30cb497fe1
Author: Gustavo Henrique Nihei <gustavo.nihei@espressif.com>
Date: Tue Jul 13 19:33:12 2021 -0300
mtd: Add MTDIOC_ERASESTATE command for retrieving erase state value
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>