ARROW-4049: [C++] Arrow never use glog even though glog is linked.

[sarutak]

The following is a part of arrow/util/logging.cc.

#ifdef ARROW_USE_GLOG
typedef google::LogMessage LoggingProvider;
#else
typedef CerrLog LoggingProvider;
#endif

As you see, when ARROW_USE_GLOG is defined, glog is intended to be used but it's not never defined and glog is never used.

I've fixed this by adding add_definition command when CMake variable ARROW_USE_GLOG is ON.

[codecov-io]

Codecov Report

Merging #3196 into master will increase coverage by 1.06%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3196      +/-   ##
==========================================
+ Coverage   86.42%   87.48%   +1.06%     
==========================================
  Files         504      446      -58     
  Lines       69623    65862    -3761     
==========================================
- Hits        60172    57620    -2552     
+ Misses       9354     8242    -1112     
+ Partials       97        0      -97

Impacted Files	Coverage Δ
go/arrow/array/table.go
go/arrow/math/uint64_amd64.go
go/arrow/internal/testing/tools/bool.go
go/arrow/internal/bitutil/bitutil.go
go/arrow/memory/memory_avx2_amd64.go
go/arrow/array/null.go
go/arrow/datatype_nested.go
go/arrow/array/string.go
go/arrow/math/uint64_avx2_amd64.go
go/arrow/array/builder.go
... and 50 more

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[wesm]

+1. Thanks for catching this!