[jdk16] RFR: 8258419: RSA cipher buffer cleanup

[Weijun Wang]

Some array allocation is not necessary, and the content can be cleaned.

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Commit messages:
 - 8258419: RSA cipher buffer cleanup

Changes: https://git.openjdk.java.net/jdk16/pull/26/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16&pr=26&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8258419
  Stats: 89 lines in 3 files changed: 34 ins; 17 del; 38 mod
  Patch: https://git.openjdk.java.net/jdk16/pull/26.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16 pull/26/head:pull/26

PR: https://git.openjdk.java.net/jdk16/pull/26