RFR: 8372565: Convert SATBMarkQueue to use Atomic<T>

[Aleksey Shipilev]

On Thu, 27 Nov 2025 08:26:15 GMT, Kim Barrett <kbarrett at openjdk.org> wrote:

> Please review this change to SATBMarkQueue to use Atomic rather than directly
> applying AtomicAccess to volatile members.
> 
> Testing: mach5 tier1-5

Marked as reviewed by shade (Reviewer).

-------------

PR Review: https://git.openjdk.org/jdk/pull/28525#pullrequestreview-3516013673