* archive.c: Include hashtab.h.

	* archive.c: Include hashtab.h.
	(struct ar_cache): Rename `arelt' to `arbfd' and remove `next'.
	(_bfd_look_for_bfd_in_cache): Reimplement using htab_find.
	(hash_file_ptr): New function.
	(eq_file_ptr): Likewise.
	(_bfd_add_bfd_to_archive_cache): Reimplement using a hash table.
	* libbfd-in.h: Include hashtab.h.
	(struct artdata): Change `cache' member type to htab_t.
	* libbfd.h: Rebuild.