xfs_scrub: detect infinite loops when scanning inodes

xfs_scrub: detect infinite loops when scanning inodes

During an inode scan (aka phase 3) when we're scanning the inode btree
to find files to check, make sure that each invocation of inumbers
actually gives us an inobt record with a startino that's at least as
large as what we asked for so that we always make forward progress.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>