RFR: 8315818: vmTestbase/nsk/jvmti/Allocate/alloc001/alloc001.java fails on libgraal [v2]

[Doug Simon]

> This PR modifies eager JVMCI initialization such that a failure is logged but otherwise ignored if the initialization is solely for the purpose of `-Xcomp`.
> 
> This allows tests such as `vmTestbase/nsk/jvmti/Allocate/alloc001/alloc001.java` to succeed on libgraal, even when there is insufficient virtual memory to mmap libgraal.

Doug Simon has updated the pull request incrementally with one additional commit since the last revision:

  instead of eagerly initializing JVMCI for -Xcomp, defer JVMCI compilations until JVMCI is initializable

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Changes:
  - all: https://git.openjdk.org/jdk/pull/15602/files
  - new: https://git.openjdk.org/jdk/pull/15602/files/038d1521..b32a7a3d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15602&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15602&range=00-01

  Stats: 46 lines in 4 files changed: 13 ins; 30 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/15602.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15602/head:pull/15602

PR: https://git.openjdk.org/jdk/pull/15602