journal: consistently allow type==0 to mean "any type"

journal: consistently allow type==0 to mean "any type"

If type==0 and a non-NULL object were given as arguments to
journal_file_hmac_put_object(), its object type check would fail and it
would return -EBADMSG.

All existing callers use either a positive type or -1. Still, for
behavior consistency with journal_file_move_to_object() let's allow
type 0 to pass.