build: re-run the code-generator when headers change

codegenerator.mk

@@ -27,14 +27,16 @@ GENERATED += $(GENDIR)/AddonModuleXbmcplugin.cpp
 GENERATED += $(GENDIR)/AddonModuleXbmcaddon.cpp
 GENERATED += $(GENDIR)/AddonModuleXbmcvfs.cpp
 
+GENERATE_DEPS += $(TOPDIR)/xbmc/interfaces/legacy/*.h
+
 vpath %.i $(INTERFACES_DIR)/swig
 
 $(GENDIR)/%.cpp: $(GENDIR)/%.xml $(JAVA) $(SWIG) $(DOXY_XML_PATH)
 	$(JAVA) -cp "$(GROOVY_DIR)/groovy-all-1.8.4.jar:$(GROOVY_DIR)/commons-lang-2.6.jar:$(TOPDIR)/tools/codegenerator:$(INTERFACES_DIR)/python" \
           groovy.ui.GroovyMain $(TOPDIR)/tools/codegenerator/Generator.groovy $< $(INTERFACES_DIR)/python/PythonSwig.cpp.template $@ $(DOXY_XML_PATH)
 	rm $<
 
-$(GENDIR)/%.xml: %.i $(SWIG) $(JAVA)
+$(GENDIR)/%.xml: %.i $(SWIG) $(JAVA) $(GENERATE_DEPS)
 	mkdir -p $(GENDIR)
 	$(SWIG) -w401 -c++ -o $@ -xml -I$(TOPDIR)/xbmc -xmllang python $<