This is a trivial fix which adds more details about the constant MTLVC_MAX_INDEX. This had come up during the review of [JDK-8261632](https://bugs.openjdk.java.net/browse/JDK-8261632).
------------- Commit messages: - Add details about MTLVC_MAX_INDEX Changes: https://git.openjdk.java.net/jdk/pull/8592/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8592&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8261650 Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/8592.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/8592/head:pull/8592 PR: https://git.openjdk.java.net/jdk/pull/8592
