RFR: [leyden] Do not enable -XX:AOTMode=on by default

[Ioi Lam]

During early Leyden development, we decided to make `-XX:AOTMode=on` the default to make it easier to diagnose mismatches between training and production runs. However, this make it impossible to run the `make test JTREG=AOT_JDK...` tests:


$ make test JTREG=AOT_JDK=onestep TEST=open/test/hotspot/jtreg/runtime/invokedynamic
[...]
Running test 'jtreg:open/test/hotspot/jtreg/runtime/invokedynamic'
[0.010s][error][aot] An error has occurred while processing the AOT cache. Run with -Xlog:aot for details.
[0.010s][error][aot] Mismatched values for property jdk.module.addexports: java.base/jdk.internal.foreign=ALL-UNNAMED,java.base/jdk.internal.misc=ALL-UNNAMED specified during runtime but not during dump time
[0.010s][error][aot] Disabling optimized module handling
[0.010s][error][aot] AOT cache has aot-linked classes. It cannot be used when archived full module graph is not used.
[0.011s][error][aot] Unable to map shared spaces
failed to get JDK properties:


Now people should be familiar with using the AOT cache, so this nanny mode isn't necessary more.

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

Commit messages:
 - Do not enable -XX:AOTMode=on by default, so that we can run "make test JTREG=AOT_JDK=onestep TEST=..."

Changes: https://git.openjdk.org/leyden/pull/82/files
  Webrev: https://webrevs.openjdk.org/?repo=leyden&pr=82&range=00
  Stats: 5 lines in 1 file changed: 0 ins; 5 del; 0 mod
  Patch: https://git.openjdk.org/leyden/pull/82.diff
  Fetch: git fetch https://git.openjdk.org/leyden.git pull/82/head:pull/82

PR: https://git.openjdk.org/leyden/pull/82