Android requested that the wpa_supplicant go upstream. This change adds
some dummy functions and reinstates DSA_dup_DH in order to make the diff
smaller and easier for upstream.

Change-Id: I77ac271b8652bae5a0bbe16afde51d9096f3dfb5
Reviewed-on: https://boringssl-review.googlesource.com/1740
Reviewed-by: Adam Langley <agl@google.com>

This change causes (EC)DSA nonces be to calculated by hashing the
message and private key along with entropy.

Initial fork from f2d678e6e8 (1.0.2 beta).

(This change contains substantial changes from the original and
effectively starts a new history.)