[aat] Tweak a couple sanitize calls that are never called

src/hb-aat-layout-common.hh

@@ -464,7 +464,8 @@ enum { DELETED_GLYPH = 0xFFFF };
 template <typename T>
 struct Entry
 {
-  bool sanitize (hb_sanitize_context_t *c, unsigned int count) const
+  // This does seem like it's ever called.
+  bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
     /* Note, we don't recurse-sanitize data because we don't access it.
@@ -492,7 +493,8 @@ struct Entry
 template <>
 struct Entry<void>
 {
-  bool sanitize (hb_sanitize_context_t *c, unsigned int count /*XXX Unused?*/) const
+  // This does seem like it's ever called.
+  bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
     return_trace (c->check_struct (this));