arrow

GH-39270: [C++] Avoid creating memory manager instance for every buffer view/copy (#39271)

### Rationale for this change

We can use `arrow::default_cpu_memory_manager()` for `default_memory_pool()`.

### What changes are included in this PR?

Check the given `pool` and use `arrow::default_cpu_memory_manager()` if it's `arrow::default_memory_pool()`.

This also caches `arrow::CPUDevice::memory_manager()` result to avoid calling it multiple times. Note that we can avoid creating needless memory manager instance without this. This just avoid calling it multiple times.

### Are these changes tested?

Yes.

### Are there any user-facing changes?

No.
* Closes: #39270

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>