RFR: 8347570: Configure fails on macOS if directory name do not have correct case

[Magnus Ihse Bursie]

If you have a directory `OpenJDK` and do `cd openjdk`, this will register the current directory as `openjdk`, not `OpenJDK`. This will later on make the check in configure to see if we are in the root directory (to determine where to put the configuration) will fail, since it does a case-sensitive comparison.

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Commit messages:
 - 8347570: Configure fails on macOS if directory name do not have correct case

Changes: https://git.openjdk.org/jdk/pull/25146/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25146&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8347570
  Stats: 21 lines in 1 file changed: 16 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/25146.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25146/head:pull/25146

PR: https://git.openjdk.org/jdk/pull/25146