!dropme Bug 2024724 - Fix PowerCounters.h because we do not compile...

!dropme Bug 2024724 - Fix PowerCounters.h because we do not compile PowerCounters-win.cpp against __MINGW32__ r=canaltinova,profiler-reviewers

BB 44868: Backport upstream commit to fix Windows builds

This commit should be dropped during the 151 rebase as it was reverted
as part of https://bugzilla.mozilla.org/show_bug.cgi?id=2026031 in the
upstream 151 branch.