fix change logs

Author: bobzhang

Changes

@@ -91,7 +91,7 @@ OCaml 4.04.0:
 
 - GPR#473: Provide `Sys.backend_type` so that user can write backend-specific
  code in some cases (for example, code generator).
- (Hongbo Zhang, review by Damien Doligez, Alain Frisch, and Hugo Heuzard)
+ (Hongbo Zhang)
 
 - PR#6820, GPR#560: Add Obj.reachable_words to compute the
  "transitive" heap size of a value
@@ -610,7 +610,7 @@ OCaml 4.03.0 (25 Apr 2016):
 * GPR#442, caml_fill_string, and caml_create_string is deprecated 
  and will be removed in the future, please use caml_fill_bytes 
  and caml_create_bytes for migration 
- (Hongbo Zhang)
+ (Hongbo Zhang, review by Damien Doligez, Alain Frisch, and Hugo Heuzard)
 
 - PR#3612, PR#92: allow allocating custom block with finalizers
  in the minor heap.