RFR: 8335358 - alternative ways to trigger the end of training run

[Mat Carter]

AOT training can be ended using either

- -XX: AOTEndTrainingOnMethodEntry =Hello.someMethod [same syntax as CompileOnly]
- -XX: AOTEndTrainingOnMethodEntry =Hello.someMethod,Hello.someOtherMethod,count=42
- jcmd AOT.end_training

supports arm64 and x64

note: the AOTEndTrainingOnMethodEntry is ignored when CDSPreImage is specified; this is needed as the phase2 forked java process is passed all phase1 flags along with the -XX:CDSPreImage, but we don't want to run the trigger code in this phase (there may be a better way to handle this state or simply remove the flag from the forked process)

JBS Issue: https://bugs.openjdk.org/browse/JDK-8335358

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Commit messages:
 - whitespace fixes
 - For c1 and c2 we add the trigger test at code gen, interpreter cant do this as method_entry are shared.
 - Consistant naming and remove debug code
 - the core trigger method should not be counted, but the compiled code call it indirectly predicated by the counter.  This is so that jcmd works and is NOT predicated on any counter value
 - Added optional count parameter
 - ignore AOTCreateOnMethodEntry when CDSPreimage is specified
 - fixed patch merge issue
 - added support for x86
 - fixed c1 and c2 issues
 - fixed patch issues
 - ... and 6 more: https://git.openjdk.org/leyden/compare/cf036d70...ad3d6f18

Changes: https://git.openjdk.org/leyden/pull/21/files
  Webrev: https://webrevs.openjdk.org/?repo=leyden&pr=21&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335358
  Stats: 277 lines in 28 files changed: 260 ins; 0 del; 17 mod
  Patch: https://git.openjdk.org/leyden/pull/21.diff
  Fetch: git fetch https://git.openjdk.org/leyden.git pull/21/head:pull/21

PR: https://git.openjdk.org/leyden/pull/21