XLOG_STATE_DO_CALLBACK is only entered through XLOG_STATE_DONE_SYNC
and just used in a single debug check.  Remove the flag and thus
simplify the calling conventions for xlog_state_do_callback and
xlog_state_iodone_process_iclog.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>