MSVC: EXPORT macro fixes

plugins/SpectrumAnalyzer/SpectrumAnalyzer.cpp

@@ -163,7 +163,7 @@ extern "C"
 {
 
 // necessary for getting instance out of shared lib
-Plugin * PLUGIN_EXPORT lmms_plugin_main( Model* parent, void* data )
+PLUGIN_EXPORT Plugin * lmms_plugin_main( Model* parent, void* data )
 {
 	return new SpectrumAnalyzer( parent, static_cast<const Plugin::Descriptor::SubPluginFeatures::Key *>( data ) );
 }