RFR: 8171508: os::jvm_path: error in handling -Dsun.java.launcher.is_altjvm option after 8066474 [v2]

[Calvin Cheung]

> This change fixes two issues in `os::jvm_path()`:
> 
> - go back 4 instead of 5 slashes and then checking for "/jre/lib";
> - fix the hardcoded "hotspot" sub-directory before the jvm library name.
> 
> Passed tiers 1 - 3 testing.

Calvin Cheung has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - @tstuefe and @dholmes-ora comments
 - Merge branch 'master' into 8171508-os-jvm_path
 - 8171508: os::jvm_path: error in handling -Dsun.java.launcher.is_altjvm option after 8066474

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/24310/files
  - new: https://git.openjdk.org/jdk/pull/24310/files/04f09cc4..eb20233a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24310&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24310&range=00-01

  Stats: 10506 lines in 190 files changed: 6408 ins; 3262 del; 836 mod
  Patch: https://git.openjdk.org/jdk/pull/24310.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24310/head:pull/24310

PR: https://git.openjdk.org/jdk/pull/24310