[jdk17u-dev] RFR: 8301187: Memory leaks in OopMapCache

[Aleksey Shipilev]

Clean backport to eliminate a minor memory leak.

Additional testing:
 - [ ] Linux AArch64 fastdebug `tier1 tier2 tier3`

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Commit messages:
 - Backport e2a3b20ca80186a3d3d1a2a9029036b088b3fc9c

Changes: https://git.openjdk.org/jdk17u-dev/pull/1412/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1412&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301187
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1412.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1412/head:pull/1412

PR: https://git.openjdk.org/jdk17u-dev/pull/1412