Avoid the use of a DH object in tls_construct_cke_dhe()
Avoid the use of a DH object in tls_construct_cke_dhe()

There is no need for us to downgrade the EVP_PKEY into a DH object
for this function so we rewrite things to avoid it.

Reviewed-by: Richard Levitte <5fb523282dd7956571c80524edc2dccfa0bd8234@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13368)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl