* cppfiles.c (file_hash_hash): New static function.
(hash_string_eq): Renamed static function to file_hash_eq.
(_cpp_init_files): Create file_hash table with above callbacks.
(cpp_included): Must use htab_find_with_hash insead of htab_find.
(_cpp_find_find, make_cpp_dir): Must use htab_find_slot_with_hash.
From-SVN: r74350
