defconfig: Enable CONFIG_F2FS_CHECK_FS for bengal

This change enables CONFIG_F2FS_CHECK_FS to check
FS consistency at runtime and catch errors.

Change-Id: I3d7ea7c4deaf84e51c557a3175f3d6e9d4b336db
Signed-off-by: Sayali Lokhande <sayalil@codeaurora.org>