Two members are only used in code that's conditioned on pseudo-feature
fslibs, which was defined in qfilesystemengine_win.cpp; move that
definition to qfiledevice_p.h so that the members's existence can be
conditioned on the same #if-ery as their use. The bootstrap build was
broken by the warning.
In the code that uses them, a lambda captured this but didn't use it,
causing the non-bootstrap build to get a warning (hence error) and
fail. So remove the unnecessary capture. Also suppressed warnings on
an unused function.
This amends commit 174af05400
Pick-to: 6.3
Task-number: QTBUG-79750
Change-Id: Ib29f3200b7736bc07df68aeec4fc6f568c8f4ddb
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
Reviewed-by: Ievgenii Meshcheriakov <ievgenii.meshcheriakov@qt.io>
aa4a2bb1e1