[jdk11u-dev] RFR: 8284756: [11u] Remove unused isUseContainerSupport in CgroupV1Subsystem

[Severin Gehwolf]

Please review this trivial clean-up. The method declaration isn't used nor implemented. The actual native method in use is in `CgroupsMetrics.java`. `TestUseContainerSupport` of container tests continue to pass.

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Commit messages:
 - 8284756: [11u] Remove unused isUseContainerSupport in CgroupV1Subsystem

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/1033/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=1033&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284756
  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/1033.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/1033/head:pull/1033

PR: https://git.openjdk.java.net/jdk11u-dev/pull/1033