ceph: normalize 'delta' parameter usage in check_quota_exceeded
Function check_quota_exceeded() uses delta parameter only for the
QUOTA_CHECK_MAX_BYTES_OP operation. Using this parameter also for
MAX_FILES will makes the code cleaner and will be required to support
cross-quota-tree renames.
Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>