RFR: 8369734: JvmtiExport::post_class_file_load_hook return value is never used [v4]

[Francesco Andreuzzi]

> The return value of `JvmtiExport::post_class_file_load_hook` is never used, so we can remove the related dead code.
> 
> Passes tier1 and tier2 (fastdebug).

Francesco Andreuzzi has updated the pull request incrementally with one additional commit since the last revision:

  restore comment

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Changes:
  - all: https://git.openjdk.org/jdk/pull/27777/files
  - new: https://git.openjdk.org/jdk/pull/27777/files/8f7f0feb..37817420

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27777&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27777&range=02-03

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/27777.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27777/head:pull/27777

PR: https://git.openjdk.org/jdk/pull/27777