Now that we track what sort of NEGOTIATE response was received, stop
mandating that every session on a socket use the same type of auth.

Push that decision out into the session setup code, and make the sectype
a per-session property. This should allow us to mix multiple sectypes on
a socket as long as they are compatible with the NEGOTIATE response.

With this too, we can now eliminate the ses->secFlg field since that
info is redundant and harder to work with than a securityEnum.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <smfrench@gmail.com>