zone: remove old function declaration

Change-Id: I2532a02610b91fd11d162136fda3ac2322d45766

src/knot/zone/zone-load.h

@@ -94,17 +94,6 @@ int knot_zload_open(zloader_t **loader, const char *source, const char *origin,
  */
 knot_zone_t *knot_zload_load(zloader_t *loader);
 
-/*!
- * \brief Checks whether the compiled zone needs a recompilation.
- *
- * \param loader Zone loader instance.
- *
- * \retval 1 is if needs to be recompiled.
- * \retval 0 if it is up to date.
- */
-//TODO will not work, has to look at serials probably
-int knot_zload_needs_update(zloader_t *loader);
-
 /*!
  * \brief Free zone loader.
  *