RFR: 8315875: GenShen: Remove heap mode check from ShenandoahInitLogger [v3]

[William Kemper]

> There are some additional improvements to the init logger that should be easy to upstream.

William Kemper has updated the pull request incrementally with one additional commit since the last revision:

  Fix zero build

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Changes:
  - all: https://git.openjdk.org/shenandoah/pull/320/files
  - new: https://git.openjdk.org/shenandoah/pull/320/files/9960fe7d..6e1d7bc8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=shenandoah&pr=320&range=02
 - incr: https://webrevs.openjdk.org/?repo=shenandoah&pr=320&range=01-02

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/shenandoah/pull/320.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah.git pull/320/head:pull/320

PR: https://git.openjdk.org/shenandoah/pull/320