Update vestigial comment from very old Info-ZIP deflate.

trees.c

 /* trees.c -- output deflated data using Huffman coding
- * Copyright (C) 1995-2016 Jean-loup Gailly
+ * Copyright (C) 1995-2017 Jean-loup Gailly
  * detect_data_type() function provided freely by Cosmin Truta, 2006
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
@@ -906,7 +906,7 @@ void ZLIB_INTERNAL _tr_align(s)
 
 /* ===========================================================================
  * Determine the best encoding for the current block: dynamic trees, static
- * trees or store, and output the encoded block to the zip file.
+ * trees or store, and write out the encoded block.
  */
 void ZLIB_INTERNAL _tr_flush_block(s, buf, stored_len, last)
     deflate_state *s;