Makefile mac: fixed bundling

fixed when lib exists but is an empty dir

Also it seems that 'cond && consequent' syntax was incorrect here,
because if cond is false, it stops current make target.

Makefile.in

@@ -654,7 +654,7 @@ $(GUI_BUNDLE)/Contents/libs: $(BUNDLE)/Contents/libs $(GUI_BUNDLE)
 	$(MKDIR_P) $(GUI_BUNDLE)/Contents/Frameworks $(GUI_BUNDLE)/Contents/libs
 	echo quit | $(DYLIBBUNDLER) $(DYLIBBUNDLER_FLAGS) -of -p @executable_path/../libs/ -cd -b -x $(GUI_BUNDLE)/Contents/MacOS/uv-qt -d $(GUI_BUNDLE)/Contents/libs/; \
 	cp $(BUNDLE)/Contents/MacOS/* $(GUI_BUNDLE)/Contents/MacOS/
-	[ -d $(BUNDLE)/Contents/libs ] && cp $(BUNDLE)/Contents/libs/* $(GUI_BUNDLE)/Contents/libs
+	[ "$$(printf $(BUNDLE)/Contents/libs/*)" = $(BUNDLE)'/Contents/libs/*' '] || cp $(BUNDLE)/Contents/libs/* $(GUI_BUNDLE)/Contents/libs
 	[ -d $(BUNDLE)/Contents/share ] && { mkdir -p $(GUI_BUNDLE)/Contents/share; cp -r $(BUNDLE)/Contents/share/* $(GUI_BUNDLE)/Contents/share; }
 	cp -R $(BUNDLE)/Contents/Frameworks/* $(GUI_BUNDLE)/Contents/Frameworks
 	# add Qt frameworks