RFR: 8289780: Remove Forte::register_stub

[David Holmes]

On Wed, 6 Jul 2022 00:38:14 GMT, Ioi Lam <iklam at openjdk.org> wrote:

> I removed `Remove Forte::register_stub` since it's used only by the Solaris Forte(TM) Performance Tools collector, which is no longer supported by the JDK.
> 
> I also fixed a couple of places where the stub name is computed unnecessarily.
> 
> Also renamed some `#ifndef IA64` around the code that I touched.

Cleanup looks good! Thanks.

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Marked as reviewed by dholmes (Reviewer).

PR: https://git.openjdk.org/jdk/pull/9386