FreeType: Fix type of glyphIdArray (cmap format 0), see merge request !515.

Both the Microsoft OpenType specification and Apple's TrueType reference
manual define the relevant field, glyphIndexArray aka glyphIdArray, as
an array of 256 bytes (aka uint8_t).

components/freetype/ttcmap.pas

@@ -36,7 +36,7 @@ type
   (* the glyphIdArray for this format has 256 entries      *)
 
   TCMap0 = record
-             glyphIdArray : PUShort;
+             glyphIdArray : PByte;
            end;
 
   (* FORMAT 2 *)