libquota: fix quota_inode_truncate()

We failed to clear EXT2_FLAG_SUPER_ONLY after deleting the
quota inode and so, the updated block bitmap was not written
back. This caused fsck to complain after running
'tune2fs -O ^quota <dev>'. Clear this flag so that updated
block bitmap gets written. Also, avoid truncating the quota
inode if it is not hidden.

Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
1 file changed