When the log is shut down all iclogs are in the XLOG_STATE_IOERROR state,
which means that xlog_state_want_sync and xlog_state_release_iclog are
no-ops. Remove the whole section of code.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>