[bdf, cid, pfr, winfonts] Improve rejection of other font formats.

This is mainly for better diagnostics of malformed fonts.

* src/bdf/bdflib.c (_bfd_readstream): Stop font format testing if the first
input line is too long or doesn't end with `\r` or `\n`.

* src/cid/cidparse.c (cid_parser_new): Don't handle too short input as an
error but as an unknown format.

* src/pfr/pfrobjs.c (pfr_face_init): Ditto.

* src/winfonts/winfnt.c (fnt_font_load, fnt_face_get_dll_font): Ditto.
4 files changed