RFR: JDK-8273959: Some metaspace diagnostic switches should be develop

[Jie Fu]

On Sat, 18 Sep 2021 08:37:38 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

> May I have reviews please for this fix.
> 
> The switches `MetaspaceHandleDeallocations` and `MetaspaceGuardAllocations` control debug-only features and consequently should be develop instead.
> 
> Unnecessary usage of -XX:+UnlockDiagnosticVMOptions is removed (in two cases unrelated to the changed switches).

LGTM

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Marked as reviewed by jiefu (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/5573