minor, use LOffsetTo and LArrayOf whenever possible (#966)

diff --git a/src/hb-open-file-private.hh b/src/hb-open-file-private.hh
index ac02752..28f967d 100644
--- a/src/hb-open-file-private.hh
+++ b/src/hb-open-file-private.hh
@@ -234,7 +234,7 @@
   Tag		ttcTag;		/* TrueType Collection ID string: 'ttcf' */
   FixedVersion<>version;	/* Version of the TTC Header (1.0),
 				 * 0x00010000u */
-  ArrayOf<LOffsetTo<OffsetTable>, HBUINT32>
+  LArrayOf<LOffsetTo<OffsetTable> >
 		table;		/* Array of offsets to the OffsetTable for each font
 				 * from the beginning of the file */
   public: