Revert commit 4a56d9a2

We have been unable to trace the contributor of that code to gain their
agreement for the licence change so the code has to be removed.

This commit reverts that contribution. The contribution had no functional
impact so the original way of doing things is still valid. However the
surrounding code has changed significantly so that the exact code as it
was orignally cannot be used. This commit uses the original code as a basis,
but rewrites it to use the PACKET API.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5808)