RFR: 8310591: Missing `@since` tags in java.lang.foreign [v3]

[Per Minborg]

> This PR adds missing  `@Since` and `@PreviewFeature` annotations to some of the Panama FFM entities.
> 
> This PR should also be back-ported to 21.

Per Minborg has updated the pull request incrementally with one additional commit since the last revision:

  Revert "Harmonize copyringht messages"
  
  This reverts commit 2931c8c7e677431c49f194fa67265005725dbcf9.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/14611/files
  - new: https://git.openjdk.org/jdk/pull/14611/files/3e35dc05..d40f5c6c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14611&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14611&range=01-02

  Stats: 271 lines in 13 files changed: 41 ins; 40 del; 190 mod
  Patch: https://git.openjdk.org/jdk/pull/14611.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14611/head:pull/14611

PR: https://git.openjdk.org/jdk/pull/14611