Jerry Jelinek got a fish trophy!
11541 allocation_classes feature must be enabled to add log device
Review Request #2222 - Created Aug. 13, 2019 and submitted
This is a minor fix so that the allocation_class feature does not have to be enabled in order to add a log device to a pool.
zfs-test run, plus a manual sequence to create a test zpool without the allocation class feature enabled, then successfully add a log device.