RFR: 8378348: Obsolete ParallelRefProcEnabled

[Joel Sikström]

On Fri, 20 Feb 2026 13:05:01 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Obsolete `ParallelRefProcEnabled`, which has `true` as its default value, for GCs (Parallel and G1) supporting this flag.
> 
> Test: tier1-5

Looks good

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

Marked as reviewed by jsikstro (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/29845#pullrequestreview-3839643483