zdb: show dedup table and log attributes

There's interesting info in there that is going to help with
understanding dedup behavior at any given moment.

Since this is a format change, tests that rely on that output have been
modified to match.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #16755