RFR: 8335688: Fix -Wzero-as-null-pointer-constant warnings from fflush calls in jvmti tests

[Coleen Phillimore]

On Thu, 4 Jul 2024 12:15:09 GMT, Kim Barrett <kbarrett at openjdk.org> wrote:

> Please review this change to some jvmti tests, which were calling fflush with
> an argument of 0. Most of these are in C++ code, where we change them to use
> nullptr as the argument.  A couple are in C, where we change them to use NULL.
> This removes a bunch of -Wzero-as-null-pointer-constant when building with
> that enabled.
> 
> Testing: mach5 tier1

Looks good.

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Marked as reviewed by coleenp (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/20032#pullrequestreview-2166246812