Fixed: [Yang identityref XML encoding is not general](https://github.com/clicon/clixon/issues/90)

* Revisiting this issue now seems to work, there are no regressions that fail when disabling IDENTITYREF_KLUDGE.

lib/src/clixon_validate.c

@@ -275,9 +275,7 @@ validate_identityref(cxobj     *xt,
     if (prefix == NULL)
         ymod = ys_module(ys);
     else{ /* from prefix to name */
-#if 1 /* IDENTITYREF_KLUDGE  */
         ymod = yang_find_module_by_prefix_yspec(ys_spec(ys), prefix);
-#endif
     }
     if (ymod == NULL){
         cprintf(cberr, "Identityref validation failed, %s not derived from %s in %s.yang:%d",