xfs: update ctime and mtime on clone destinatation inodes

We're changing both metadata and data, so we need to update the
timestamps for clone operations.  Dedupe on the other hand does
not change file data, and only changes invisible metadata so the
timestamps should not be updated.

This follows existing btrfs behavior.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: remove redundant is_dedupe test]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>