Adopt compact form.

Machines/PCCompatible/PCCompatible.cpp

@@ -942,10 +942,10 @@ std::unique_ptr<Machine> Machine::PCCompatible(
 	const ROMMachine::ROMFetcher &rom_fetcher
 ) {
 	const Target *const pc_target = dynamic_cast<const Target *>(target);
-
+	using VideoAdaptor = Target::VideoAdaptor;
 	switch(pc_target->adaptor) {
-		case Target::VideoAdaptor::MDA:	return machine<Target::VideoAdaptor::MDA>(*pc_target, rom_fetcher);
-		case Target::VideoAdaptor::CGA:	return machine<Target::VideoAdaptor::CGA>(*pc_target, rom_fetcher);
+		case VideoAdaptor::MDA:	return machine<VideoAdaptor::MDA>(*pc_target, rom_fetcher);
+		case VideoAdaptor::CGA:	return machine<VideoAdaptor::CGA>(*pc_target, rom_fetcher);
 		default: return nullptr;
 	}
 }