Sapphire v2.5.9 - fixed build problem for Windows.

There was a compatibility problem between MINGW and
my own member function named `format`. I don't need MINGW
so I disabled it in the Cardinal Makefile.

This solution was suggested by @falkTX.
It is nice because I don't have to change any Sapphire code!

plugins/Makefile

@@ -2763,6 +2763,7 @@ $(BUILD_DIR)/Sapphire/%.cpp.o: Sapphire/%.cpp
 	@echo "Compiling $<"
 	$(SILENT)$(CXX) $< $(BUILD_CXX_FLAGS) -std=gnu++17 -c -o $@ \
 		$(foreach m,$(SAPPHIRE_CUSTOM),$(call custom_module_names,$(m),Sapphire)) \
+		-DSKIP_MINGW_FORMAT \
 		-DpluginInstance=pluginInstance__sapphire
 
 $(BUILD_DIR)/sonusmodular/%.cpp.o: sonusmodular/%.cpp