[C++] CpuInfo.Basic test fails on newer Apple silicon CPUs due to unexpectedly large L2 CPU cache

[matshch]

Describe the bug, including details regarding any error messages, version, and platform.

Here is the error that we see on our Apple M2 machine:

/tmp/nix-build-arrow-cpp-20.0.0.drv-0/source/cpp/src/arrow/util/io_util_test.cc:1099: Failure
Value of: l2 >= 32 * 1024 && l2 <= 12 * 1024 * 1024
  Actual: false
Expected: true
unexpected L2 size: 16777216
[  FAILED  ] CpuInfo.Basic (0 ms)

As far as I can see, there are CPUs in the wild with up to 64 MiB of L2 CPU cache, so it should be allowed.

Component(s)

C++

[raulcd]

Seems in-line with the change we did when we added macOS M1:

• GH-40082: [CI][C++] Add a job on ARM64 macOS #40456

[pitrou]

A funny one @AntoinePrv

[matshch]

I'm not sure it is good to have such limitations at all, but at least we should update them.

[kou]

Issue resolved by pull request 47563
#47563