arrow

GH-40398: [C++] Expose protobuf dependency if opentelemetry or ORC are enabled (#40399)

### Rationale for this change

When not bundling dependencies, `libarrow.a` depends on protobuf symbols if built with ORC or opentelemetry support. However this dependency was not looked up in ArrowConfig.cmake, causing client projects using linking to `arrow_static` to fail in configuration.

### What changes are included in this PR?

This change makes it so that the dependency on `protobuf` is propagated to the installed `ArrowConfig.cmake` file when necessary.
* GitHub Issue: #40398

Authored-by: Tobias Mayer <tobim@fastmail.fm>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>