RFR: 8304681: compiler/sharedstubs/SharedStubToInterpTest.java fails after JDK-8304387

[Xiaolin Zheng]

Please review this test fix for [JDK-8304387](https://bugs.openjdk.org/browse/JDK-8304387) after RFR.

Instead of specifying shared stubs' locations in this test, we could check if two or more relocations combined with each of them in this test, same as the other test `SharedTrampolineTest.java`. The counting logic is aligned with `SharedTrampolineTest.java`. Printing relocation stuff requires debug version vm, so this test is changed to debug only. Also some minor cleanups for the tests.

Apologies for the tier2 failure. I mainly focused on if there were new hs_errs when working on JDK-8304387. :-(

I am now confirming if the comment "Static stubs must be created at the end of the Stub section" could be removed, which needs a little extra time - though I think we can relax such limitations in `SharedStubToInterpTest.java`.
-- Update on March 27th: comfirmed; please see the JBS issue for the discussion.

Tested x86_64, AArch64 and RISC-V for tests under `compiler/sharedstubs` folder, and now all passed (release, fastdebug).

Thanks,
Xiaolin

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Commit messages:
 - Test fixes after JDK-8304387

Changes: https://git.openjdk.org/jdk/pull/13135/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13135&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304681
  Stats: 60 lines in 3 files changed: 3 ins; 49 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/13135.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13135/head:pull/13135

PR: https://git.openjdk.org/jdk/pull/13135