make EVP_PKEY opaque

Reviewed-by: Richard Levitte <levitte@openssl.org>
diff --git a/crypto/evp/p_dec.c b/crypto/evp/p_dec.c
index f232934..218c674 100644
--- a/crypto/evp/p_dec.c
+++ b/crypto/evp/p_dec.c
@@ -72,7 +72,7 @@
     int ret = -1;
 
 #ifndef OPENSSL_NO_RSA
-    if (priv->type != EVP_PKEY_RSA) {
+    if (EVP_PKEY_id(priv) != EVP_PKEY_RSA) {
 #endif
         EVPerr(EVP_F_EVP_PKEY_DECRYPT_OLD, EVP_R_PUBLIC_KEY_NOT_RSA);
 #ifndef OPENSSL_NO_RSA
@@ -80,7 +80,8 @@
     }
 
     ret =
-        RSA_private_decrypt(ekl, ek, key, priv->pkey.rsa, RSA_PKCS1_PADDING);
+        RSA_private_decrypt(ekl, ek, key, EVP_PKEY_get0_RSA(priv),
+                            RSA_PKCS1_PADDING);
  err:
 #endif
     return (ret);