RFR: 8333093: Incorrect comment in zAddress_aarch64.cpp

[Ashutosh Mehra]

This PR is just updating the comments, so no need for any testing.

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Commit messages:
 - 8333093: Incorrect comment in zAddress_aarch64.cpp

Changes: https://git.openjdk.org/jdk/pull/19428/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19428&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333093
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19428.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19428/head:pull/19428

PR: https://git.openjdk.org/jdk/pull/19428