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

[Iris Clark]

On Wed, 7 May 2025 21:25:39 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

> `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.

Verified 15 uses of `$(ECHO) -n` introduced by [8301197](https://bugs.openjdk.org/browse/JDK-8301197) ([PR 24415](https://github.com/openjdk/jdk/pull/24415)) reverted.

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Marked as reviewed by iris (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/25106#pullrequestreview-2823459609