RFR: 8326590: Improve description of MarkStackSize[Max] flags

[Thomas Schatzl]

Hi all,

  please review this changes to the description of `MarkStackSize[Max]` to add the unit of the given value.

Testing: local compilation

Thanks,
  Thomas

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Commit messages:
 - Add unit

Changes: https://git.openjdk.org/jdk/pull/18003/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18003&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326590
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/18003.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18003/head:pull/18003

PR: https://git.openjdk.org/jdk/pull/18003