GH-47914: [C++] Fix system Apache ORC/Google logging used detection

[kou]

Rationale for this change

We need to use orc_SOURCE not ORC_SOURCE for Apache ORC and glog_SOURCE not GLOG_SOURCE for Google logging.

What changes are included in this PR?

Fix referred variable names.

Are these changes tested?

Yes in apache/arrow-java#865 .

Are there any user-facing changes?

Yes.

• GitHub Issue: [C++] System Apache ORC used detection is broken #47914

[github-actions]

⚠️ GitHub issue #47914 has been automatically assigned in GitHub to PR creator.

[raulcd]

@github-actions crossbow submit -g cpp

[raulcd]

👍 LGTM, will merge once CI finishes if successful

[github-actions]

Revision: 1cef7e1

Submitted crossbow builds: ursacomputing/crossbow @ actions-11243595d4

Task	Status
example-cpp-minimal-build-static
example-cpp-minimal-build-static-system-dependency
example-cpp-tutorial
test-build-cpp-fuzz
test-conda-cpp
test-conda-cpp-valgrind
test-cuda-cpp-ubuntu-22.04-cuda-11.7.1
test-debian-12-cpp-amd64
test-debian-12-cpp-i386
test-fedora-42-cpp
test-ubuntu-22.04-cpp
test-ubuntu-22.04-cpp-20
test-ubuntu-22.04-cpp-bundled
test-ubuntu-22.04-cpp-emscripten
test-ubuntu-22.04-cpp-no-threading
test-ubuntu-24.04-cpp
test-ubuntu-24.04-cpp-bundled-offline
test-ubuntu-24.04-cpp-gcc-13-bundled
test-ubuntu-24.04-cpp-gcc-14
test-ubuntu-24.04-cpp-minimal-with-formats
test-ubuntu-24.04-cpp-thread-sanitizer

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 4 benchmarking runs that have been run so far on merge-commit 603901a.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 10 possible false positives for unstable benchmarks that are known to sometimes produce them.