RFR: 8332678: Serial: Remove use of should_clear_all_soft_refs in serial folder

[Ivan Walulya]

On Wed, 22 May 2024 09:43:20 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple removing all accesses to `soft_ref_policy` in Serial code, because the decision to clear-soft-refs is made inside Serial and captured in local variables.

Trivial

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Marked as reviewed by iwalulya (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/19346#pullrequestreview-2080569808