Use the normal OpenSSL function instead of the crypto wrapper (#629)

We don’t support 0.9.8 anymore.
diff --git a/src/OpenSSL/crypto.py b/src/OpenSSL/crypto.py
index 98a7c78..3ef0e9b 100644
--- a/src/OpenSSL/crypto.py
+++ b/src/OpenSSL/crypto.py
@@ -309,7 +309,7 @@
 
         :return: The type of the key.
         """
-        return _lib.Cryptography_EVP_PKEY_id(self._pkey)
+        return _lib.EVP_PKEY_id(self._pkey)
 
     def bits(self):
         """