arrow

GH-41367: [C++] Replace [[maybe_unused]] with Arrow macro (#41359)



### Rationale for this change

This is a follow up to https://github.com/apache/arrow/pull/41111 which was created as an issue in #41367

### What changes are included in this PR?

Replace [[maybe_unused]] with Arrow macro

### Are these changes tested?

Builds cleanly

### Are there any user-facing changes?

No

* GitHub Issue: #41367

Authored-by: Will Ayd <william.ayd@icloud.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>