Document and add macros for additional DSA options

Document and add macros for additional DSA options

EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS and EVP_PKEY_CTRL_DSA_PARAMGEN_MD are only
exposed from EVP_PKEY_CTX_ctrl, which means callers must write more error-prone
code (see also issue #1319). Add the missing wrapper macros and document them.

Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit a97faad76a1be22eadd6c1a39972ad5e095d9e80)

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/10094)