LU-12950 osd-ldiskfs: increase supported size to 1024tb

LU-12950 osd-ldiskfs: increase supported size to 1024tb

Currently attempts of creating ldisk file system with size >512TB
finished with message:

    LDISKFS-fs does not support file systems greater than 512TB
    and can cause data corruption. Use "force_over_512tb" mount
    option to override.

Change "force_over_512tb" mount option to "force_over_1024tb" as
testing for these large filesystems have not shown any serious
functional problems (though there are performance issues to address).

Test-Parameters: trivial fstype=ldiskfs testlist=conf-sanity
Signed-off-by: Artem Blagodarenko <c17828@cray.com>
Cray-bug-id: lus-6815
Change-Id: I0f84fe85aaab05ab0bafa5f0e6074e1690d79899
Reviewed-on: https://review.whamcloud.com/36705
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>