RFR: 8354278: Revert use of non-POSIX echo -n introduced in JDK-8301197

[Magnus Ihse Bursie]

`echo -n` is not part of the required POSIX standard, and built in shell versions of echo might not support it. Restore the previous use of `printf` instead.

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Commit messages:
 - 8354278: Revert use of non-POSIX echo -n introduced in JDK-8301197

Changes: https://git.openjdk.org/jdk/pull/25106/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25106&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354278
  Stats: 17 lines in 5 files changed: 0 ins; 0 del; 17 mod
  Patch: https://git.openjdk.org/jdk/pull/25106.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25106/head:pull/25106

PR: https://git.openjdk.org/jdk/pull/25106