RFR: 8326959: Improve JVMCI option help [v6]

[Doug Simon]

> This PR improves the wording and layout of JVMCI options exposed to users.
> All other JVMCI options are no longer included in the output of `-XX:+JVMCIPrintProperties`.
> 
> 
>> java -XX:+JVMCIPrintProperties
> [JVMCI properties]
> jvmci.Compiler = null                                                     [String]
>           Selects the system compiler. This must match the getCompilerName() value
>           returned by a jdk.vm.ci.runtime.JVMCICompilerFactory provider.
>           An empty string or the value "null" selects a compiler
>           that raises an exception upon receiving a compilation request.
> 
> jvmci.PrintConfig = false                                                [Boolean]
>           Prints VM values (e.g. flags, constants, field offsets etc) exposed to JVMCI.

Doug Simon 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 six additional commits since the last revision:

 - Merge remote-tracking branch 'openjdk-jdk/master' into JDK-8326959
 - more minor edits for clarity
 - removed extra space
 - improved layout of help for jvmci.Compiler option
 - add new line after each JVMCI option help
 - improve help text for some JVMCI options and removed help from internal options

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18045/files
  - new: https://git.openjdk.org/jdk/pull/18045/files/52c20847..ed5abd81

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18045&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18045&range=04-05

  Stats: 2563 lines in 805 files changed: 653 ins; 284 del; 1626 mod
  Patch: https://git.openjdk.org/jdk/pull/18045.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18045/head:pull/18045

PR: https://git.openjdk.org/jdk/pull/18045