check_f2fs: return 0 all the time

It reports any errors with message, so we don't need to return -1 which
results in check_f2fs.sh exit.

Change-Id: I59ac6d441d24e96900783852f61ec778b08d8cee
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
1 file changed