We currently flag setlocale(...) as locale dependent, but prior to this commit we didn't flag
std::locale::global(...) as such.

In addition to setting the global C++ locale std::locale::global(...) also does the equivalent
of std::setlocale(LC_ALL, ...);.

Thus the functionality of std::locale::global(...) is a superset of setlocale(...) :)

This is a backport of core#18649

arc lint --everything