RFR: 8263635: Add --prefix option to jhsdb debugd

[Yasumasa Suenaga]

`jhsdb debugd` supports server name prefix with `sun.jvm.hotspot.rmi.serverNamePrefix` system property. It will be used as remote name for SA remote object. It is "SARemoteDebugger" by default.

As a result, remote name will be constructed as following:


//host[:port]/<serverNamePrefix>['_'<id>]


However we have no way to set it excepting system property. jhsdb should provide the way to set it as a command line option. And also we should add the way to specify the prefix when we connect to debug server. I will add it like `--connect id at server:1234/prefix`.

I've also filed [CSR for this PR](https://bugs.openjdk.java.net/browse/JDK-8265897). Please review it.
This PR modifies DisableRegistryTest.java, but it has been addressed in ProblemList-zgc.txt now. So this PR does not affect ZGC.

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Commit messages:
 - 8263635: Add --prefix option to jhsdb debugd

Changes: https://git.openjdk.java.net/jdk/pull/3669/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3669&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263635
  Stats: 59 lines in 5 files changed: 27 ins; 14 del; 18 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3669.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3669/head:pull/3669

PR: https://git.openjdk.java.net/jdk/pull/3669