e2scrub: remove -C from e2scrub_all

We already have the "SERVICE_MODE=1" feature that signals to e2scrub
that we're running as a background daemon and therefore we should exit
quietly if conditions aren't right.

It's therefore unnecessary to have a separate -C flag to achieve the
same outcome for cron jobs.  Merge the two together.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
5 files changed