Annotate gtk_ordering_from_cmpfunc as skip

We do extra work here to make the introspection scanner pick up
the docs for the static inline function, but that doesn't make the
function actually work in language bindings, so mark it as skip.

Fixes: #6298

gtk/gtkenums.h

@@ -681,7 +681,7 @@ typedef enum {
 GtkOrdering     gtk_ordering_from_cmpfunc       (int cmpfunc_result);
 #else
 /**
- * gtk_ordering_from_cmpfunc:
+ * gtk_ordering_from_cmpfunc: (skip)
  * @cmpfunc_result: Result of a comparison function
  *
  * Converts the result of a `GCompareFunc` like strcmp() to a

gtk/gtksorter.c

@@ -372,7 +372,7 @@ gtk_sorter_changed_with_keys (GtkSorter       *self,
  */
 #ifdef __GI_SCANNER__
 /**
- * gtk_ordering_from_cmpfunc:
+ * gtk_ordering_from_cmpfunc: (skip)
  * @cmpfunc_result: Result of a comparison function
  *
  * Converts the result of a `GCompareFunc` like strcmp() to a