RFR: 8355223: Improve documentation on @IntrinsicCandidate [v8]

[Chen Liang]

> In offline discussion, we noted that the documentation on this annotation does not recommend minimizing the intrinsified section and moving whatever can be done in Java to Java; thus I prepared this documentation update, to shrink a "TLDR" essay to something concise for readers, such as pointing to that list at `vmIntrinsics.hpp` instead of "a list".

Chen Liang has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 12 additional commits since the last revision:

 - Separate design doc
 - Merge branch 'master' of https://github.com/openjdk/jdk into doc/intrinsic-candidate
 - More review updates
 - Merge branch 'master' of https://github.com/openjdk/jdk into doc/intrinsic-candidate
 - Move intrinsic to be a subsection; just one most common function of the annotation
 - Merge branch 'master' of https://github.com/openjdk/jdk into doc/intrinsic-candidate
 - Merge branch 'master' of https://github.com/openjdk/jdk into doc/intrinsic-candidate
 - Update src/java.base/share/classes/jdk/internal/vm/annotation/IntrinsicCandidate.java
   
   Co-authored-by: Raffaello Giulietti <raffaello.giulietti at oracle.com>
 - Shorter first sentence
 - Updates, thanks to John
 - ... and 2 more: https://git.openjdk.org/jdk/compare/0d5ea5a0...e4afa49d

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/24777/files
  - new: https://git.openjdk.org/jdk/pull/24777/files/a312d92b..e4afa49d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24777&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24777&range=06-07

  Stats: 348197 lines in 6043 files changed: 206814 ins; 98457 del; 42926 mod
  Patch: https://git.openjdk.org/jdk/pull/24777.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24777/head:pull/24777

PR: https://git.openjdk.org/jdk/pull/24777