builtin/pack-objects.c: use ALLOC_GROW() in check_pbase_path()

Signed-off-by: NDmitry S. Dolzhenko <dmitrys.dolzhenko@yandex.ru>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin/pack-objects.c

@@ -1156,12 +1156,9 @@ static int check_pbase_path(unsigned hash)
 	if (0 <= pos)
 		return 1;
 	pos = -pos - 1;
-	if (done_pbase_paths_alloc <= done_pbase_paths_num) {
-		done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
-		done_pbase_paths = xrealloc(done_pbase_paths,
-					    done_pbase_paths_alloc *
-					    sizeof(unsigned));
-	}
+	ALLOC_GROW(done_pbase_paths,
+		   done_pbase_paths_num + 1,
+		   done_pbase_paths_alloc);
 	done_pbase_paths_num++;
 	if (pos < done_pbase_paths_num)
 		memmove(done_pbase_paths + pos + 1,