Add missing MAX macros, ensure that i3 can be compiled without pango

src/util.c

@@ -341,10 +341,12 @@ char *pango_escape_markup(char *input) {
     if (!font_is_pango())
         return input;
 
+#if PANGO_SUPPORT
     char *escaped = g_markup_escape_text(input, -1);
     FREE(input);
 
     return escaped;
+#endif
 }
 
 /*