builtin-remote: refactor duplicated cleanup code

This patch moves identical lines of code into a cleanup function. The
function has two callers and is about to gain a third.

Also removed a bogus NEEDSWORK comment per Daniel Barkalow:

  Actually, the comment is wrong; "remote" comes from remote_get(),
  which returns things from a cache in remote.c; there could be a
  remote_put() to let the code know that the caller is done with the
  object, but it wouldn't presently do anything.

Signed-off-by: Jay Soffian <jaysoffian@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-remote.c

@@ -632,6 +632,13 @@ static void show_list(const char *title, struct string_list *list,
 		printf("    %s\n", list->items[i].string);
 }
 
+static void free_remote_ref_states(struct ref_states *states)
+{
+	string_list_clear(&states->new, 0);
+	string_list_clear(&states->stale, 0);
+	string_list_clear(&states->tracked, 0);
+}
+
 static int get_remote_ref_states(const char *name,
 				 struct ref_states *states,
 				 int query)
@@ -738,10 +745,7 @@ static int show(int argc, const char **argv)
 			}
 		}
 
-		/* NEEDSWORK: free remote */
-		string_list_clear(&states.new, 0);
-		string_list_clear(&states.stale, 0);
-		string_list_clear(&states.tracked, 0);
+		free_remote_ref_states(&states);
 	}
 
 	return result;
@@ -792,10 +796,7 @@ static int prune(int argc, const char **argv)
 			warn_dangling_symref(dangling_msg, refname);
 		}
 
-		/* NEEDSWORK: free remote */
-		string_list_clear(&states.new, 0);
-		string_list_clear(&states.stale, 0);
-		string_list_clear(&states.tracked, 0);
+		free_remote_ref_states(&states);
 	}
 
 	return result;