Add a test for xfsdump -D, which skips unchanged directories during
an incremental backup. After doing an initial backup, a new file is
added to one directory (to verify that changed directories are
backed up) and several files are appended to. Then an incremental
backup is done with -D set. The test verifies the original and
restored filesystems match after applying the base and incremental
backups, and that the incremental restore output indicates that only
the one changed directory was backed up.
Signed-off-by: Bill Kendall <wkendall@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de>