RFR: 8274851: [PPC64] Port zgc to linux on ppc64le [v3]

[Niklas Radomski]

> Port the Z garbage collector ([JDK-8209683](https://bugs.openjdk.java.net/browse/JDK-8209683)) to linux on ppc64le.

Niklas Radomski has updated the pull request incrementally with three additional commits since the last revision:

 - Remove superfluous copyright change
 - Fix predicate conditions
 - Add ByteSize constructor to Address

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/5842/files
  - new: https://git.openjdk.java.net/jdk/pull/5842/files/5da8c1b7..052ad5c8

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=5842&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=5842&range=01-02

  Stats: 9 lines in 3 files changed: 3 ins; 0 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5842.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5842/head:pull/5842

PR: https://git.openjdk.java.net/jdk/pull/5842