[woff] Optimize table tagging.

* include/freetype/internal/wofftypes.h (WOFF_TableRec): Use
32-bit tag.
* src/sfnt/sfwoff.c (woff_open_font): Use 32-bit tag.

include/freetype/internal/wofftypes.h

@@ -92,7 +92,7 @@ FT_BEGIN_HEADER
    */
   typedef struct  WOFF_TableRec_
   {
-    FT_ULong  Tag;           /* table ID                  */
+    FT_Tag    Tag;           /* table ID                  */
     FT_ULong  Offset;        /* table file offset         */
     FT_ULong  CompLength;    /* compressed table length   */
     FT_ULong  OrigLength;    /* uncompressed table length */

src/sfnt/sfwoff.c

@@ -109,7 +109,7 @@
     FT_ULong        sfnt_offset;
 
     FT_Int          nn;
-    FT_ULong        old_tag = 0;
+    FT_Tag          old_tag = 0;
 
     static const FT_Frame_Field  woff_header_fields[] =
     {