RFR: 8265967: Unused NullCheckNode forward declaration in node.hpp

[Vladimir Kozlov]

On Mon, 26 Apr 2021 11:44:22 GMT, Tobias Hartmann <thartmann at openjdk.org> wrote:

> Please review this trivial change that removes the forward declaration of a nonexistent `NullCheckNode`.
> 
> Thanks,
> Tobias

Trivial.

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Marked as reviewed by kvn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3691