RFR: 8346232: Remove leftovers of the jar --normalize feature

[Eirik Bjørsnøs]

Please review this cleanup PR which removes a property and a code comment left behind after the `jar --normalize` feature  was removed in JDK 14.

The feature was deprecated in JDK-8199871 and removed in JDK-8234542, along with removal of Pack200 tools and APIs.

This PR removes the now unused `main.help.opt.create.normalize` property and a code comment in `Main.java` referencing normalization.

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Commit messages:
 - Remove leftovers from the --normalize feature

Changes: https://git.openjdk.org/jdk/pull/22751/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22751&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346232
  Stats: 25 lines in 12 files changed: 0 ins; 15 del; 10 mod
  Patch: https://git.openjdk.org/jdk/pull/22751.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22751/head:pull/22751

PR: https://git.openjdk.org/jdk/pull/22751