[C++, lint] Use clang-format more efficiently in `check-format` target

[asfimport]

clang-format supports command line option -output-replacements-xml which (in the case of no required changes) outputs:

<?xml version='1.0'?>
<replacements xml:space='preserve' incomplete_format='false'>
</replacements>

Using this option during check-format instead of using python to compute a diff between formatted and on-disk should speed up that target significantly

Reporter: Ben Kietzman / @bkietz

_{Note: This issue was originally created as ARROW-4515. Please see the migration documentation for further details.}

[github-actions[bot]]

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