VST: Export "main" on non-windows, fixes discovery for bitwig

distrho/src/DistrhoPluginVST.cpp

@@ -954,6 +954,13 @@ static void vst_processReplacingCallback(AEffect* effect, float** inputs, float*
 
 END_NAMESPACE_DISTRHO
 
+DISTRHO_PLUGIN_EXPORT
+#if DISTRHO_OS_WINDOWS
+const AEffect* VSTPluginMain(audioMasterCallback audioMaster);
+#else
+const AEffect* VSTPluginMain(audioMasterCallback audioMaster) asm ("main");
+#endif
+
 DISTRHO_PLUGIN_EXPORT
 const AEffect* VSTPluginMain(audioMasterCallback audioMaster)
 {
@@ -1016,3 +1023,5 @@ const AEffect* VSTPluginMain(audioMasterCallback audioMaster)
 
     return effect;
 }
+
+// -----------------------------------------------------------------------