RFR: 8331008: Implement JEP 478: Key Derivation Function API (Preview) [v63]

[Kevin Driver]

> Introduce an API for Key Derivation Functions (KDFs), which are cryptographic algorithms for deriving additional keys from a secret key and other data. See [JEP 478](https://openjdk.org/jeps/478).

Kevin Driver has updated the pull request incrementally with one additional commit since the last revision:

  expand javadoc wrt addIKM and addSalt; also provide HKDFParameterSpec creation examples

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Changes:
  - all: https://git.openjdk.org/jdk/pull/18924/files
  - new: https://git.openjdk.org/jdk/pull/18924/files/0a360256..2919bfe5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18924&range=62
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18924&range=61-62

  Stats: 62 lines in 2 files changed: 56 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/18924.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18924/head:pull/18924

PR: https://git.openjdk.org/jdk/pull/18924