Allow static plugin builds to have JACK driver

Signed-off-by: falkTX <falktx@falktx.com>

source/backend/engine/CarlaEngineNative.cpp

@@ -3089,7 +3089,9 @@ CARLA_BACKEND_START_NAMESPACE
 
 namespace EngineInit {
 
+#ifndef HAVE_JACK
 CarlaEngine* newJack() { return nullptr; }
+#endif
 
 #ifdef USING_JUCE_AUDIO_DEVICES
 CarlaEngine*       newJuce(const AudioApi)           { return nullptr; }

source/backend/engine/Makefile

@@ -117,12 +117,12 @@ ifeq ($(MACOS),true)
 $(OBJDIR)/CarlaEngineNative.cpp.exp.o: CarlaEngineNative.cpp
 	-@mkdir -p $(OBJDIR)
 	@echo "Compiling CarlaEngineNative.cpp (plugin)"
-	$(SILENT)$(CXX) $< $(BUILD_CXX_FLAGS) -DCARLA_PLUGIN_BUILD -ObjC++ -c -o $@
+	$(SILENT)$(CXX) $< $(BUILD_CXX_FLAGS) -DCARLA_PLUGIN_BUILD -UHAVE_JACK -ObjC++ -c -o $@
 else
 $(OBJDIR)/CarlaEngineNative.cpp.exp.o: CarlaEngineNative.cpp
 	-@mkdir -p $(OBJDIR)
 	@echo "Compiling CarlaEngineNative.cpp (plugin)"
-	$(SILENT)$(CXX) $< $(BUILD_CXX_FLAGS) -DCARLA_PLUGIN_BUILD -c -o $@
+	$(SILENT)$(CXX) $< $(BUILD_CXX_FLAGS) -DCARLA_PLUGIN_BUILD -UHAVE_JACK -c -o $@
 endif
 
 ifeq ($(JACKBRIDGE_DIRECT),true)