[jdk11u-dev] RFR: 8273526: Extend the OSContainer API pids controller with pids.current

[Matthias Baesken]

backport of 8273526, os_linux.cpp and src/hotspot/os/linux/cgroupV2Subsystem_linux.cpp changes had to manually adjusted.

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Commit messages:
 - Backport d4546b6b36f9dc9ff3d626f8cfe62b62daa0de01

Changes: https://git.openjdk.org/jdk11u-dev/pull/1172/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1172&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8273526
  Stats: 90 lines in 14 files changed: 87 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1172.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1172/head:pull/1172

PR: https://git.openjdk.org/jdk11u-dev/pull/1172