RFR: 8347606: Optimize Java implementation of ML-DSA [v3]

[Ben Perez]

> It turns out that initializing a multidimensional array with `int[][] a = new int[rows][cols]` is slower than allocating each column in a loop. Since we do a lot of large multidimensional array allocations in ML-DSA, the optimized initialization improves performance by roughly 10%.

Ben Perez has updated the pull request incrementally with one additional commit since the last revision:

  remove trailing whitespace

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23642/files
  - new: https://git.openjdk.org/jdk/pull/23642/files/7ed6dbc4..886cc263

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23642&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23642&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/23642.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23642/head:pull/23642

PR: https://git.openjdk.org/jdk/pull/23642