[FT] Just return if glyph name not found

The fallback happens in higher level already.  No need to do here.

src/hb-ft.cc

@@ -242,8 +242,8 @@ hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED,
   FT_Face ft_face = (FT_Face) font_data;
 
   hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size);
-  if (!ret || (size && !*name))
-    snprintf (name, size, "gid%u", glyph);
+  if (ret && (size && !*name))
+    ret = false;
 
   return ret;
 }