RFR: 8365190: Remove LockingMode related code from share [v3]

[Coleen Phillimore]

On Thu, 4 Sep 2025 12:07:43 GMT, Fredrik Bredberg <fbredberg at openjdk.org> wrote:

>> Since the integration of [JDK-8359437](https://bugs.openjdk.org/browse/JDK-8359437) the `LockingMode` flag can no longer be set by the user. After that, a number of PRs has been integrated which has removed all `LockingMode` related code from all platforms (except from zero, which is done in this PR).
>> 
>> This PR removes `LockingMode` related code from the shared (non-platform specific) files. It also removes the `LockingMode` variable itself.
>> 
>> Passes tier1-tier5 with no added problems.
>
> Fredrik Bredberg has updated the pull request incrementally with one additional commit since the last revision:
> 
>   New version for Coleen

Looks great!!

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Marked as reviewed by coleenp (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27041#pullrequestreview-3184882023