Mark a HelloRequest record as read if we ignore it

Otherwise the client will try to process it again. The second time around
it will try and move the record data into handshake fragment storage and
realise that there is no data left. At that point it marks it as read
anyway. However, it is a bug that we go around the loop a second time, so
we prevent that.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2200)