[foreign-memaccess+abi] RFR: Change classes into records and fix finality [v2]

[Per Minborg]

On Mon, 19 Sep 2022 14:49:08 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

>> I will hold back the other splittings. Can we accept the ones here to move forward?
>
> No. We don't have consensus on whether these changes are good or bad, so we should not just move forward with them. We're not in a hurry.

I will revert the formatting so we can get this PR through. We could introduce the reformatting in a separate PR should we decide to do it.

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PR: https://git.openjdk.org/panama-foreign/pull/725