RFR: 8256485: Zero VM build broken after JDK-8254231

[Aleksey Shipilev]

On Tue, 17 Nov 2020 17:12:30 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

> JDK-8254231 breaks the Zero VM build. This PR contains fixes to get it working again.
> 
> Testing: Building zero VM variant on Linux.

I am going to approve this even in the draft form. The draft patch fixes x86_64 Zero builds for me, and this unblocks pending Zero work. Of course, it does not make new `java/foreign` tests pass, but that is something we can deal with later.

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Marked as reviewed by shade (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/1265