[cid] Signedness revisions.

Unsigned checks are simpler.

* include/freetype/t1tables.h (CID_FaceInfoRec): Change to unsignd
`num_dicts`.
* src/cid/cidparse.h (CID_Parser): Change to unsigned `num_dict`.

* src/cid/cidgload.c (cid_load_glyph): Updated.
* src/cid/cidload.c (cid_load_keyword, parse_fd_array,
parse_expansion_factor, parse_font_name, cid_read_subrs,
cid_face_open): Updated.
* src/cid/cidobjs.c (cid_face_done): Updated.
* src/cid/cidparse.c (cid_parser_new): Updated.
6 files changed