RFR: 8309605: StubRoutines are not used by SA

[Coleen Phillimore]

Please remove this trivial fix to remove StubRoutines that the SA doesn't use.
Tested serviceability/sa tests.

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Commit messages:
 - 8309605: StubRoutines are not used by SA

Changes: https://git.openjdk.org/jdk/pull/14519/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14519&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309605
  Stats: 69 lines in 1 file changed: 0 ins; 68 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/14519.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14519/head:pull/14519

PR: https://git.openjdk.org/jdk/pull/14519