EVP: Expand the use of EVP_PKEY_CTX_md()

EVP: Expand the use of EVP_PKEY_CTX_md()

Setting a hash function was reserved for signature operations.
However, it turns out that SM2 uses a hash function for encryption and
decryption as well.
Therefore, EVP_PKEY_CTX_md() must be called with an expanded operation
type combination that includes EVP_PKEY_OP_TYPE_CRYPT when used in a
generic way.

For SM2, test/recipes/30-test_evp_data/evppkey_sm2.txt is expanded to
test decryption both with an implicit and an explicit digest.

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12789)