xfs: test larger dump/restore to/from file

xfs: test larger dump/restore to/from file

This test creates a large-ish directory structure using
fsstress, and does a dump/restore to make sure we dump
all the files.

Without the fix for the regression caused by:
c7cb51d xfs: fix error handling at xfs_inumbers

we will see failures like:

    -xfsrestore: 486 directories and 1590 entries processed
    +xfsrestore: 30 directories and 227 entries processed

as it fails to process all inodes.

I think that existing tests have a much smaller set of files,
and so don't trip the bug.

I don't do a file-by-file comparison here, because for some
reason the diff output gets garbled; this test only checks
that we've dumped & restored the correct number of files.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>