refs: docstring typo

Signed-off-by: Tao Qingyun <taoqy@ls-a.me>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs/refs-internal.h

@@ -281,7 +281,7 @@ int refs_rename_ref_available(struct ref_store *refs,
  *
  *             // Access information about the current reference:
  *             if (!(iter->flags & REF_ISSYMREF))
- *                     printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
+ *                     printf("%s is %s\n", iter->refname, oid_to_hex(iter->oid));
  *
  *             // If you need to peel the reference:
  *             ref_iterator_peel(iter, &oid);