-Y option for zdb is valid
The -Y option was added for ztest to test split block reconstruction.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Signed-off-by: Igor Kozhukhov <igor@dilos.org>
Closes #8926