Verifying a Wii game creates an instance of IOS, and Dolphin
can't handle more than one instance of IOS at the same time.
Properly supporting it is probably more effort than it's worth.
Fixes https://bugs.dolphin-emu.org/issues/12494.
While manually capturing constexpr variables used in lambda
expressions does work, it's really easy to forget doing so since
we don't have a Windows CMake builder and the workaround isn't
necessary anywhere else. Fortunately, MSVC has a flag that fixes
the constexpr capture behavior, so let's use that instead.
Lambda expressions with uncaptured constants were leading to errors,
and there were also some warnings about deprecated functions
(QFontMetrics::width and inet_ntoa).
The case body is empty because VolumeVerifier doesn't actually report
problems with severity of None.
Fixes "warning: enumeration value ‘None’ not handled in switch [-Wswitch]"
warning reported by gcc.
JosJuice